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L.  B.   Cat.  No.   II37 


'  The  first  farmer  was  the  first  man.  and  all  historic 
nobility  rests  on  possession  and  use  of  land." 

— Emerson. 


LIPPINCOTT^S  COLLEGE  TEXTS 

AGRICULTURE 

EDITED  BY 

KARY  C.  DAVIS,  Ph.D. 

PROFESSOR    OF   AGRICULTURE,    KNAPP    SCHOOL    OF   COUNTRY   LIFE,    GEORGE    PBABODY 

COLLEGE  FOR  TEACHERS,    NASHVILLE,    TENNESSEE;     AUTHOR  OF 

PRODUCTIVE  FARMING,  HORTICULTURE,  ETC. 


THE  POTATO 

ITS  CULTURE,   USES,    HISTORY    AND   CLASSIFICATION 

By  WILLIAM  STUART 

HORTICULTURIST,  U.  S.  DEPARTMENT   OF    AGRICULTURE 


LiPPiNCOTT's  Farm  Manuals 

Edited  by  K.  C.  DAVIS.  Ph.D.,  Knapp  School  of  Country  Life,  Nashville,  Tenn. 
Every  effort  is  made  to  keep  these  standard  te.xts  up-to-date,  and 
new  editions  are  published  and  revisions  made  whenever  necessary. 

PRODUCTIVE  SWINE  HUSBANDRY 

By  GEORGE  E.  DAY,  B.S.A.     Third  Edition,  Revised 

PRODUCTIVE  POULTRY  HUSBANDRY 

By  HARRY  R.  LEWIS,  M.Agr.     Fourth  Edition,  Revised  and  Enlarged 

PRODUCTIVE  HORSE  HUSBANDRY 

By  CARL  W.  GAY,  D.V.M.,  B.S.A.     Third  Edition,  Revised 

PRODUCTIVE  ORCHARDING 

By  FRED  C.  SEARS,  M.S.     Second  Edition,  Revised 

PRODUCTIVE  VEGETABLE  GROWING 

By  JOHN  W.  LLOYD,  M.S. A.    Third  Edition  Revised 

PRODUCTIVE  FEEDING  OF  FARM  ANIMALS 

By  F.  W.  WOLL,  Ph.D.,  Third  Edition,  Revised 
C0A4M0N  DISEASES  OF  FARM  ANIMALS 

By  R.  A.  CRAIG,  D.V.M.,  Third  Edition,  Revised 

PRODUCTIVE  FARM  CROPS 

By  E.  G.  MONTGOMERY.  M.A.     Third  Edition,  Revised 

PRODUCTIVE  BEE  KEEPING 

By  FRANK  C.  PELLETT.     Second  Edition,  Revised 

PRODUCTIVE  DAIRYING 

By  R.   M.  WASHBURN,   M.S.A.     Second  Edition,  Revised 

INJURIOUS  INSECTS  AND  USEFUL  BIRDS 

By  F.  L.  WASHBURN.  M.A. 

PRODUCTIVE  SHEEP  HUSBANDRY 
By  WALTER  C.  COFFEY,  M.A. 

PRODUCTIVE  SMALL  FRUIT  CULTURE 

By  FRED  C.  SEARS.  M.S. 

PRODUCTIVE  SOILS 

By  WILBERT  W.  WEIR.  M.S. 

LIPPINCOTT'S  COLLEGE  TEXTS 

SOIL  PHYSICS  AND  MANAGEMENT 

By  J.  G.  MOSIER,  B.S..  A.  F.  GUSTAFSON,  M.S. 

FARM  LIFE  TEXT  SERIES 

APPLIED  ECONOMIC  BOTANY 
By  MELVILLE  T.  COOK,  Ph.D. 

PRODUCTIVE  PLANT  HUSBANDRY 

By  KARY  C.  DAVIS.     Second  Edition,  Revised 

HORTICULTURE  FOR  HIGH  SCHOOLS 

By  KARY  C.   DAVIS.     Second  Edition,  Revised 

PRODUCllVE  SOILS  (Abridged  Edition) 
By  WILBERT  W.  WEIR,  M.S. 

VOCATIONAL  CHEMISTRY 

By  J.J.  WILLAMAN 

LABORATORY  MANUALS  AND  NOTEBOOKS 

ON  THE  FOLLOWING  SUBJECTS 

SOILS,  By  J.  F.  EASTMAN  and  K.  C.  DAVIS         POULTRY,  By  H.  R   LEWIS 

DAIRYING,  By  E.  L.  ANTHONY  FEEDING,  By  F.  W.  WOLL 

FARM  CROPS,  Bv  F.  W.  LATHROP 


LIPPINCOTT'S  COLLEGE  TEXTS 

AGRICULTURE 

EDITED   BY  K.  C.  DAVIS,  Ph.D. 


THE  POTATO 

ITS  CULTURE,  USES,  HISTORY  AND 
CLASSIFICATION 


BY 


WILLIAM  STUART 

HnRTICMl.TURIST,  U.  S    DEPARTMENT  OF    AGRICULTURE 


ILLUSTRATIONS  IN  THE  TEXT 


"  If  vain  our  toil. 
We  ought  to  blame  the  culture,  not  the  soil." 

Pope — Essay  on  Man 


PHILADELPHIA  AND  LONDON 
J.  B.  LIPPINCOTT  COMPANY 


VP2^^  b 


COPYRIGHT    1923,    BY   J.    H.    LIPPINCUTT   COMPANY 


PRINTEn    BY    T.    Tt.    LIPPINCOTT   COMPANY 

AT   TIIK    WASHINGTON    SQl'ARE    PRESS 

PIlII.AnEI.PIlIA,    U.    S.    A. 


'  LIBRARY 

IV.  C.  state  College 


DEDICATED  TO  MY  DEPARTED  FRIEND  AND 
COUNSELLOR  CYRUS  GUERNSEY  PRINGLE 
WHOSE  EARLY  YEARS  WERE  DEVOTED  TO 
THE  BREEDING  OF  SUPERIOR  CEREALS, 
VEGETABLES,    AND   FRUITS. 


1044 


PREFACE 

The  great  importance  of  the  potato  as  a  human  food  in  all 
countries  having  temperate  climates  is  now  more  fully  appreciated 
than  ever  before.  The  role  that  this  crop  played  in  the  late  "World 
War,"  especially  in  Germany  and  Austria,  may  never  be  fully  rea- 
lized outside  of  these  two  countries  themselves.  Naturally,  a  crop 
of  such  great  economic  importance  as  the  potato,  and  one  having 
such  a  wide  adaptation  to  the  soil  and  climatic  conditions,  involves 
many  cultural  problems  and  has  many  enemies  in  the  shape  of 
insect  and  fungous  pests  with  which  to  contend.  The  grower  of 
this  crop,  therefore,  has  to  be  continually  on  the  alert  to  protect 
the  crop  from  injury  by  either  insects  or  disease,  and  at  the  same 
time  to  give  the  plants  good  cultural  care.  Each  year,  it  would 
seem,  brings  new  problems  for  the  scientists  to  solve.  It  is  little 
wonder,  therefore,  that  much  has  been  written  upon  the  potato 
since  it  was  first  introduced  into  Europe  from  South  America. 

In  the  preparation  of  this  book,  it  has  been  the  aim  of  the 
author  to  discuss  the  basic  principles  underlying  the  production 
of  potatoes,  as  well  as  to  include  the  latest  available  information 
in  regard  to  the  industry  as  a  whole.  No  one  appreciates  more 
keenly  than  does  the  writer  how  difficult  it  is  to  completely  cover 
all  phases  of  the  subject.  The  best  that  can  be  hoped  for  is  that 
it  will  approach  the  ideal  desired. 

No  effort  has  been  made  to  discuss  potato  production  methods 
in  foreign  countries,  and  little  is  given  concerning  the  varieties 
grown  there.  The  author's  actual  observations  and  field  studies, 
extending  over  many  years  and  many  states,  are  used  in  making 
the  treatment  of  each  topic  more  practical  and  complete. 

In  the  potato  project  outline,  given  in  the  AppendLx,  operations 


\-iii  PREFACE 

and  studies  are  given  in  seasonal  sequence,  for  the  benefit  of  the 
students  and  young  farmers  who  plan  to  grow,  for  the  first  time, 
a  crop  of  potatoes  for  profit. 

The  author  desires  to  express  his  very  great  obligation  to  the 
United  States  Department  of  Agriculture  for  a  large  share  of  the 
photographs  used  for  illustrative  purposes ;  to  many  kind  friends, 
some  of  whom  have  reviewed  certain  chapters  of  the  book,  and 
others  who  have  contributed  information  or  material  in  the  form 
of  photographs  or  literature.  To  attempt  to  enumerate  the  names 
of  all  these  would  be  difficult,  and  possibly  dangerous  in  that  some 
of  them  might  be  overlooked. 

William  Stuart. 
Washington,  D.  C. 
1923. 


CONTENTS 


Chapter  Page 
PART  I. 

I.  The  Potato  as  a  World  Crop    and  Its  Relative   Impor- 
tance IN  THE  United  States 1 

II.  Potato  Production  in  North  America 7 

III.  Leading  Environmental  Influences  in  Potato  Culture  : 

Soil,  Temperature  and  Moisture 14 

IV.  The  Soil  and  Its  Preparation  for  the  Crop 23 

V.  Food    Requirements    of    the    Potato    Crop     and     How 

Supplied 27 

VI.  Crop  Rotation 38 

VII.  Varieties  to  Grow;   Kind  and  Amount  of   Seed  to  Use, 

AND  Planting  Methods 46 

VIII.  The  Cultural  Care  of  the  Growing  Crop (J^ 

IX.  Potato  Production  in  the  South 92 

X.  Potato  Production  in  the  North  and  West 121 

XI.  Potato  Production  Costs 156 

XII.  Harvesting,  Picking  and  Handling  —  Grading,  Shipping,  and 

Marketing  the  Potato  Crop 166 

XIII.  Potato  Storage  and  Storage  Shrinkage 207 

XIV.  Types  of  Storage  Houses,  Their  Construction  and  Cost  221 

XV.  Potato  Diseases  and  Their  Control 247,. 

XVI.  Insect  and  Animal  Parasites  of  the  Potato  and  Methods 

OF  Controlling  Them 290 

XVII.  Fungicides  and  Insecticides:  Their  Preparation,  Use, 
Application,  and  Resultant  Benefits.  Spray,  Equip- 
ment and  Classification 323 

XVIII.  Industrial  Uses  of  the  Potato  in   America  and  Foreign  ^^ 

Countries ;    348 

PART  II. 

XIX.  The  Botany  of  the  Potato (^W 

XX.  Origin  and  Early  History  of  the  Potato <-  "3B9 

XXI.  Potato  Breeding  and  Selection 384 

XXII.  Classification  and  Description  of  Commercial  Varieties  435 

Appendix 475 

IX 


THE  POTATO 


CHAPTER  I 


THE  POTATO  AS  A  WORLD  CROP  AND 
RELATIVE  IMPORTANCE  IN  THE 
UNITED  STATES 


ITS 


Relative  Magnitude. — A  careful  consideration  of  the  relative 
magnitude  of  the  potato  as  a  world  crop,  reveals  the  fact  that,  from 
the  production  standpoint,  it  far  exceeds  that  of  any  other  table 
food  plant.  The  statistical  data,  presented  in  the  following  table, 
includes  the  production  of  potatoes,  oats,  corn,  wheat,  rye,  and 
barley.  The  production  of  rice  is  purposely  omitted,  owing  to 
incomplete  data;  but  there  is  every  reason  to  believe  that  if  com- 
plete statistical  information  were  available,  the  world's  rice  crop 
insofar  as  volume  of  production  is  concerned,  would  probably  be 
a  close  competitor  of  wheat.  Owing  to  the  World  War  it  has  not 
been  possible  to  secure  reliable  statistical  data  regarding  the  extent 
of  the  crops  produced  by  Germany  and  her  allies  since  1913,  hence 
the  data  presented  represents  the  average  for  the  years  1909  to 
1913  inclusive. 

A  careful  analysis  of  these  data  shows  that  the  potato  crop  far 
exceeds  that  of  the  cereal  crops. 

Comparison  of  the  average  loorld  production  of  potatoes,  oats,  corn, 
wheat,  rye,  and  barley  with  that  of  the  Ihiited  States  for  the  years  1909 
to  1913  inclusive* 


Crop 

World's  crop  in 

Per  cent,  of 

United  States  crop 

Per  cent,  by 

bushels 

total 

in  bushels 

United  States 

Potatoes . 

5,453,419,000 

26.52 

354,095,600 

6.49 

Oats  .... 

4,.323,736,000 

21.02 

1,131,219,400 

26.16 

Corn  .... 

3,807,036,000 

18.51 

2,752,371,600 

72.30 

Wheat  . . 

3,725,551,400 

18.12 

697,459,000 

18.45 

Rye 

1,788,286,600 

8.70 

35,460,000 

1.98 

Barley  . . 

1,467,505,000 

7.13 

181,273,800 

12.  35 

*From  data  given  in  the  1915  Yearbook  U.  S.  D.  A. 

This  excess  is  over  one  billion  bushels  above  that  of  oats ;  one 
and  one-half  billion  bushels  over  that  of  corn,  and  nearly  one  and 

1 


2  THE  POTATO  AS  A  WORLD  CROP 

three-quarter  billion  bushels  greater  than  that  of  wheat.  The  rye 
and  barley  crops  are  less  than  one-third  that  of  potatoes. 

A  somewhat  clearer  comprehension  of  the  relative  magnitude 
of  these  six  crops  is  obtained  from  the  graphic  chart  (Fig.  1). 

In  order  to  study  the  relative  magnitude  of  these  crops  in  the 
United  States  as  compared  with  the  world's  production,  the^o  data 
are  also  presented  in  the  preceding  table,  with  the  percentage  of 
each  crop  produced  in  this  country. 

A  study  of  these  data  shows  extremely  wide  variations  in  tlie 
^^^^^^^^^^^^^^  magnitude  of  production  and  per- 
^^^l"^^ .    ^^^^g^n^^^^^  centage.    For  example,  Avhile  this 

Cotw         ^^^^■■■^iHB  country  produces  only  about  2  per 

wheii       H^iHBHH^^i^^  Cent  of  the  world's  crop  of  rye, 

■Rv^e         ^^^^m  over  72  per  cent  of  the  corn  crop 

;BitVe3      ^^^  jg  gj-o^j^   ii^  ii^Q  United   States. 

''  The  percentage  of  the  other  crops 

Scale  1,000,000,000  bu.  to  J^inch.  •        ^  5  n  i      ^/>  ^i 

given  are  as  follows:   oats  26.16; 

Fig.    1. — World   production   of    food   crops         ,        J.^r.,vr.l        i  -.^r.-  ^   ^^ 

1009-1913.  wheat  18.72 ;  barley,  12.35 ;  while 

in  the  case  of  potatoes  the  crop  of  the  United  States  is  only  6.49 
per  cent  of  the  world's  crop. 

Home  vs  Foreign  Potato  Production. — It  is  of  considera1)le 
interest  in  the  present  study  of  the  potato  crop,  to  compare  the 
]iroduction  of  the  United  States  with  that  of  some  of  the  leading 
Foreign  potato-producing  countries,  in  order  to  study  in  greater 
detail  the  relative  position  of  each  with  respect  to  volume  of  pro- 
duction. These  data,  which  are  assembled  in  the  next  table,  are 
rather  illuminating  in  that  they  show  the  magnitude  of  the  crop 
produced  in  Germany  and  Eussia,  and  the  relatively  small  crop 
grown  in  the  United  States.  It  will  also  be  noted,  that  while  this 
country  occupies  fifth  position  both  in  acreage  and  volume  of  pro- 
duction, yet  it  is  next  to  the  lowest  in  acre  yield.  The  data  further 
shows  that  the  potato  crop  of  Germany  is  almost  five  times  greater 
than  that  of  the  United  States  for  the  years  mentioned, or, expressed 
in  percentage,  our  crop  is  but  21  per  cent  of  tlie  German  crop.  A 
study  of  the  percentage  of  the  world's  crop  of  potatoes,  produced 
by  the  countries  included  in  the  following  table,  discloses  equally 
interesting  comparisons. 

Germany's  crop  represents  30.8  per  cent  of  the  total  produc- 
tion; Kussia's  22.9;  Austria  Hungary  12.1;  France  8.9;  United 
States  6.5;  Great  Britain  4.6;  Belgium  and  the  Netherlands  each 


RELATIVE  IMPORTANCE  OF  POTATO  CROP 


about  2  per  cent.     Another  very  interesting  comparison  may  be 
made  from  these  data  relative  to  the  average  production  per  acre. 

Average  acreage  grown  and  bushels  produced  in  the  leading  potato  growing 
countries  of  Europe  and  America,  1909-1913  inclusive -^ 


Country 

(a) 
Area  in  acres 

Total  bushels 

(b) 

Average  bushels 

per  acre 

(b) 
Percentage  of 
World's  Crop 

Germany 

8,260,250 

11,127,250 

4,888,250 
3,841,000 
3,679,500 
1,169,250 
414,500 
389,e67(=) 
715,000C') 
657,500 
475,750 
379,000 
301,000 
185,667(^) 
139,667(») 

1,681,959,000 

1,251,425,600 

662,202,400 

489,376,800 

354,095,600 

254,438,200 

110,152,600 

107,021,000 

92,051,500 

60,813,400 

77,872,400 

63,759,200 

48,238,800 

40,537,400 

32,440,400 

203.6 

112.5 

135.5 
127.4 

96.2 
217.6 
265.7 
274.6 
128.7 

92.5 
163.7 
168.2 
160.3 
218.3 
232.3 

30  8 

Russia  

(European)    

Austria   \ 

22.9 

Hungary/    

France  

12.1 
9.0 

United  States 

Great  Britain  

Netherlands    

6.5 
4.7 
2.0 
2.0 

Spain   

1.7 

Italy 

1.1 
1.4 

1.2 

So.  America  (>)     

Switzerland 

0.9 
07 

0.6 

t  No  later  European  data  available.  (') 

(a)  Average  1911-191.3.  («) 

(b)  Computed  from  columns  1  and  2.  (') 
(')    Argentina  and  Chile. 

P)     1911,  1912  and  1913  data. 


1910  and  1912  data. 
1911,  1912,  and  1913  data. 
1910,  1911,  and  1912  data. 
Note.  All  data  in  columns  1  and  2  from 
the  Yearbook  of  the  U.  S.  D.  A. 


Ranked  on  this  basis,  Belgium  leads  the  list  with  an  average  of 
274.6  bushels;  the  Netherlands  come  next  with  365.7;  Denmark 
is  third  with  232.3  bushels  per  acre;  Switzerland  is  fourth  with 
218.3;  Great  Britain  fifth  with  217.6,  and  Germany  sixth  with 
203.6  bushels.  The  nine  remaining  countries  rank  as  follows : 
Sweden  168.2;  Canada  163.7;  South  America  160.3;  Austria 
Hungary  135.5;  Spain  128.7;  France  127.4;  Eussia  112.5;  United 
States  96.2;  and  Italy  92.5. 

Relative  Importance  of  the  Potato  Crop  in  the  United 
States. — As  determined  by  acreage  and  value  of  the  crop  produced, 
the  potato  occupies  sixth  place  among  the  crops  grown  in  the 
United  States.     If,  however,  it  is  considered  on  the  basis  of  a  table 


THE  POTATO  AS  A  WORLD  CROP 


gSQ 


Per  cent 

increase 

over  1910- 

1914 

period 

to 

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SS  oS  So  So  So  ss 

So  ss  ss  So  ss  ss 

a 

6 

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6 

1 

a  1 

8 

1 
.2 

RELATIVE  IMPORTANCE  OF  THE  POTATO  CROP      5 

food  i)roduct,  it  undoubtedly  is  ouly  second  to  that  of  wheat.  The 
data,  as  presented  in  the  table  {p.  4)  show  the  average  annual 
acreage,  production,  and  farm  value  of  these  six  leading  agricul- 
tural crops  in  the  United  States  for  the  two  five-year  periods  of 
1910-1914,  and  1915-1919.  It  is  clearly  evident  from  these  data 
that  the  corn  crop  is,  by  all  odds,  the  most  important.  Its  total 
value  is  greater  than  hay  and  wheat  combined,  and  is  some  seven 
times  more  valuable  than  the  potato  crop.  In  production  per  acre 
potatoes  easily  take  the  lead,  both  in  bushels  and  in  money  value. 

In   comparing  the 
ii""i^""^         money  value  of  a  crop, 
— 1^ — I  it  is  very  necessary  to 
take  into  consideration 
the  actual  cost  of  pro- 
ducing it.    For  example, 
the  cost  of  producing  a 
crop  of  wheat  or  oats  is 
necessarily    less    than 
that  of  corn;  and,  to  a 
— ^  ^"=''"'*  much  greater  extent, 

C=l    Dollars  +1,-         •        X  • 

this  IS  true  m  a  com- 

Scale  ^i  inch  400,000,000  bu.  or  dollarB.  parisOU    of    the    produC- 

FiG.  2. — Average  production  in  bushels  and   farm    tioU    COStS    of    COm    and 

value  in  dollars  Dec.   1,   for   1910-1914.  1915-1919.  potatoes.        T  h  e    potato 

crop  is  a  much  more  expensive  one  to  grow.  This  increased  cost 
is  self-evident  to  those  familiar  with  potato  production.  It  may 
be  briefly  summed  up  in  two  words,  labor  and  fertilizer.  These 
two  items  are  the  big  factors  in  the  growing  of  potatoes  in  sections 
where  commercial  fertilizers  are  used. 

The  data  in  the  table  illustrates  one  other  point  quite  as  forcibly 
as  that  of  relative  yield  and  farm  values ;  it  is  that  of  the  upward 
trend  of  prices  of  agricultural  products  during  the  last  five-year 
period.  To  the  writer,  this  is  one  of  the  most  striking  lessons 
presented  in  the  table.  With  very  little  variation  in  acre  yields, 
the  value  of  the  crops  have,  in  some  cases,  more  than  doubled. 
Corn,  for  example,  increased  over  114  per  cent;  hay  nearly  50 
per  cent;  wheat  over  91;  cotton  almost  100;  oats  nearly  72,  and 
potatoes  over  97  per  cent. 


/  1910 


6  THE  POTATO  AS  A  WORLD.CROP 

It  is  thus  apparent  that  war  conditions  enhanced  the  value  of 
agricultural  products  quite  materially. 

The  main  object  in  presenting  these  data  is,  however,  primarily 
for  the  purpose  of  comparing  the  relative  importance  of  the  potato 
crop  in  American  agriculture  in  such  a  way  as  to  permit  of  quick 
comparison  with  that  of  the  grain  crops,  corn,  wheat,  and  oats. 
This  is  well  illustrated  in  figure  2  which  graphically  represents  the 
production  and  value  of  the  corn,  wheat,  oats,  and  potato  crops 
during  the  two  five-year  periods  1910  to  1914  and  1915  to 
1919  (Fig.  2). 

QUESTIONS    ON    THE   TEXT 

1.  What    is    the    relative    magnitude    of    the    potato    when    viewed    as    a 

world  crop? 

2.  With  what  other  food  crops  is  it  compared? 

3.  Why  has  the  rice  crop  been  omitted? 

4.  What  is  the  relative  importance  of  rice  as  compared  with  wheat? 

5.  What  percentage  of  the  total  of  these  six  food  crops  consists  of  potatoes  ? 

6.  What  crop  is  next  in  percentage  of  production  to  the  potato? 

7.  Give  order  of  next  four  crops. 

8.  What  is  the  excess  production  of  potatoes  over  corn  and  wheat? 

9.  What  percentage  of  the  world's  potato   crop  does  the  United   States 

produce? 

10.  What  percentage  of  the  world's  corn  crop  does  the  United  States  produce? 

11.  What  is  the  respective  magnitude  of  the  other  four  crops  as  expressed 

in  percentages? 

12.  Wliat   position   does   the   United    States    occupy   with   other   coiuitries 

as  regards  the  magnitude  of  her  potato  crop? 

13.  What  countries  exceed  the  United  States  in  potato  production? 

14.  Name  the  six  leading  countries  in  the  order  of  their  importance  from 

the  standpoint  of  production? 

15.  Give  the  percentage  that  each  of  these  six  countries  produce. 

16.  What  country  produces  the  largest  average  yield  per  acre? 

17.  Give  the  six  leading  countries  based  on  acreage  production. 

IS.  What  position  does  the  United  States  occupy  in  yield  per  acre? 

19.  What  is  the  relative  importance,  based  on  monej^  value,  of  the  potato 

crop   in  the  United   States,   as  compared  with   corn,  hay,   wheat, 

cotton  and  oats? 


QUESTIONS  SUGGESTED  BY  THE  TEXT 

1.  What  is  the  annual  yield  of  potatoes  in  your  county  and  state? 

2.  Compare   the   yields    of   potatoes    and    six    other    important    crops    in 

your  county  and  state? 


CHAPTEE  II 

POTATO  PRODUCTION  IN  NORTH  AMERICA 

United  States  Production. — While  it  has  been  shown  in  the 
preceding  chapter  that  the  potato  crop  of  the  United  States  is 
hardly  more  than  a  drop  in  the  bucket,  as  it  were,  of  the  world's 
crop,  it  is,  nevertheless,  a  very  important  agricultural  crop  in  cer- 
tain sections  of  the  United  States  and  Canada.  Owing  to  rather 
unreliable  and  fragmentary  data  concerning  potato  production  in 
Mexico,  no  attempt  has  been  made  to  include  it  in  the  present  dis- 
cussion. The  data  presented  in  the  tables  on  pages  8  and  9  give  the 
average  acreage  and  production  for  two  five-year  periods,  1913- 
1916,  and  1915-1919,  inclusive.  The  main  object  in  presenting 
these  two  sets  of  data  is  that  of  affording  an  opportunity  to  observe 
the  changes  brought  about  in  some  sections,  as  a  result  of  war  con- 
ditions, in  the  acreage  devoted  to  potato  production.  One  of  the 
interesting  features  of  these  changes  is  that  of  the  rank  or  relative 
position  of  the  various  states  with  respect  to  the  magnitude  of  their 
production.  A  study  of  the  table  shows  that  only  three  of  the  six 
largest  producing  states  maintained  their  relative  positions  during 
the  two  five-year  periods.  These  states  were  Nev/  York,  Wisconsin, 
and  Pennsylvania.  Michigan  drops  from  second  to  fourth  place, 
Maine  from  fourth  to  fifth,  while  Minnesota  passes  from  fifth  to 
second  position.  In  the  second  group  of  six  states  the  position 
of  every  one  is  slightly  changed;  for  example,  Virginia  moves  into 
seventh  place  and  Ohio  drops  from  seventh  to  ninth;  while  Cali- 
fornia rises  from  eleventh  to  eighth  position,  and  Iowa  drops  from 
ninth  to  fourteenth  place.  While  these  changes  in  rank  are  in- 
teresting to  note,  they  are  by  no  means  vital  to  the  industry, 
except  as  they  illustrate  responses  to  economic  or  climatic  condi- 
tions, the  first  of  which  reacts  in  a  larger  or  smaller  acreage  accord- 
ing as  to  whether  the  previous  crop  brought  a  high  or  a  low  price ; 
and  the  second,  in  the  production  of  a  larger  or  smaller  number 
of  bushels  per  given  area,  as  is  evidenced  by  a  comparison  of  the 
average  yield  per  acre.  The  climatic  factor  exerts  a  much  greater 
influence  on  the  total  production  of  any  given  section  than  does  the 
ordinary  fluctuation  in  acreage,  due  to  economic  conditions.  There 
are,  of  course,  exceptions  to  the  preceding  statement,  as  was  evi- 
denced by  the  very  large  increase  in  the  1918  acreage  in  a  number 
of  the  Southern  states,  particularly  in  Florida,  due  to  the  exceed- 
ingly high  price  received  for  the  1917  crop. 

7 


Average  acreage  and  production  of  ■potatoes  by  States  for  the 

1912-1916,  inclusive 


2 
3 
4 
5 
6 
7 
8 
9 
10 
11 
12 
13 
14 
15 
16 
17 
18 
19 
20 
21 
22 
23 
24 
25 
26 
27 
28 
29 
30 
31 
32 
33 
34 
35 
36 
37 
38 
39 
40 
41 
42 
43 
44 
45 
46 
47 
48 


New  York 

Michigan 

Wisconsin 

Maine 

Minnesota 

Pennsylvania. . 

Ohio 

Virginia 

Iowa 

New  Jersey  .  .  . 

CaUfornia 

lUinois 

Washington .  .  . 

Nebraska 

Colorado 

Oregon 

North  Dakota. 

Indiana 

Missouri 

South  Dakota . 

Montana 

Idaho 

Kansas 

West  Virginia . 

Kentucky 

Maryland 

Vermont 

Utah 

Massachusetts. 


North  Carolina.  . 

Texas 

Connecticut 

Oklahoma 

New  Hampshire . 

Nevada  

Wyoming 

Arkansas 

Louisiana 

Alabama 

Florida 

Delaware 

Mississippi 

Georgia 

South  Carohna. 
New  Mexico ... 

Rhode  Island 

Arizona 


Number 
of  acres 


352,400 

347,800 

295,600 

133,600 

271,000 

270,000 

157,800 

115,400 

141,200 

91,200 

74,800 

127,400 

61,600 

113,800 

63,600 

53,400 

67,400 

77,200 

89,600 

63,600 

37,600 

31,600 

71,200 

48,200 

50,200 

42,200 

24,600 

19,800 

26,200 

36,600 

32,400 

44,600 

23,400 

32,400 

16,400 

12,400 

14,600 

25,600 

24,400 

18,200 

12,600 

10,800 

11,800 

13,600 

10,400 

8,600 

5,000 

1,000 


Number 
of  bushels 


32,485,000 

30,139,800 

28,865,400 

28,560,800 

28,223,000 

23,909,000 

12,833,600 

11,833,300 

11,247,600 

10,252,400 

9,859,400 

9,627,400 

8,884,600 

8,751,800 

7,466,000 

7,069,600 

6,712,200 

6,054,800 

5,881,000 

5,794,000 

5,449,000 

5,015,000 

4,797,400 

4,382,800 

4,078,600 

3,934,000 

3,236,600 

3,203,000 

3,159,000 

2,680,000 

2,609,200 

2,606,000 

2,479,800 

2,135,400 

2,095,400 

2,076,400 

1,946,000 

1,839,000 

1,588,600 

1,509,800 

1,009,000 

976,400 

952,000 

925,600 

820,000 

805,600 

592,000 

104,000 


Averages  and  totali- 


3,674,800 


361,450,200 


Average  acreage  and  production  of  potatoes  by  States  for  the  years 
1915-1919,  inclusive 


Number 
of  acres 


Number 
of  bushels 


Average 
bushels 
per  acre 


New  York 

Minnesota 

Wisconsin 

Michigan 

Maine 

Pennsylvania 

Virginia 

California 

Ohio 

New  Jersey 

Illinois 

Colorado 

Nebraska 

Iowa 

Washington 

Missouri 

North  Dakota 

South  Dakota 

Indiana 

Oregon 

Kentucky 

West  Virginia 

Montana 

Idaho  

Kansas 

Maryland 

North  Carohna .... 

Tennessee 

Massachusetts 

Wyoming 

Utah 

Vermont 

Alabama 

Texas 

Arkansas 

Oklahoma 

Connecticut 

New  Hampshire  .  . . 

Louisiana 

Florida 

Nevada 

South  Carolina .... 

Georgia 

Mississippi 

Delaware 

New  Mexico 

Rhode  Island 

Arizona 

Averages  and  totals 


363,600 

295,400 

299,800 

343,800 

126,200 

280,400 

139,200 

87,200 

152,600 

100,600 

143,200 

74,800 

119,600 

123,200 

64,200 

102,800 

85,400 

79,600 

89,800 

54,600 

63,400 

53,000 

46,400 

32,800 

73,400 

51,000 

48,400 

44,400 

31,200 

26,000 

20,000 

26,000 

37,000 

48,000 

37,600 

39,800 

24,400 

18,800 

31,600 

22,200 

10,600 

19,200 

19,200 

15,600 

11,400 

9,600 

5,000 

3.200 


31,843,400 

27,894,000 

27,238,000 

25,892,000 

23,309,600 

23,226,000 

15,052,000 

12,032,400 

11,037,200 

10,991,200 

10,838,000 

10,747,000 

9,688,200 

8,940,200 

8,715,200 

7,793,400 

6,564,600 

6,491,000 

6,377,000 

6,320,000 

5,585,400 

5,262,800 

5,181,000 

5,064,800 

4,943,400 

4,752,600 

4,397,000 

3,525,600 

3,451,400 

3,398,000 

3,288,800 

2,986,600 

2,934,400 

2,917,200 

2,709,200 

2,496,200 

2,279,000 

2,202,400 

2,119,600 

1,933,800 

1,922,400 

1,740,200 

1,351,200 

1,250,000 

1,027,400 

877,400 

534,000 

281.000 


87.6 
94.4 
90.9 
75.3 

184.7 
82.8 

108.1 

137.9 
72.3 

109.2 
75.7 

143.7 
81.0 
72.5 

135.8 
75.8 
76.9 
81.5 
71.0 

115.8 
88.1 
99.3 

111.7 

154.4 
67.3 
93.2 
90.8 
79.4 

110.6 

130.7 

164.4 

114.9 
79.3 
60.8 
72.1 
62.7 
93.4 

117.2 
67.1 
87.1 

181.4 
90.6 
70.4 
80.4 
90.1 
91.4 

106.8 
87.8 


3,995,200 


371,403,200 


92.9 


10  POTATO  PRODUCTION  IN  NORTH  AMERICA 

A  detailed  study  of  the  annual  acreage,  production,  average 
yield  per  acre,  and  price  per  bushel  of  potatoes  by  states  during  the 
years  1915-1919,  (see  table  in  Appendix)  shows  tliat,  with  but  few 
exceptions,  the  acreage  increase  in  1917  was  quite  marked  in  the 
North,  due  to  tlie  high  prices  received  for  the  1916  crop;  whereas, 
in  the  South  the  greatest  increase  in  acreage  occurred  in  1918, 
following,  as  has  been  previously  mentioned,  the  high  prices  re- 
ceived for  the  Southern  1917  crop.  If  we  neglect  the  years  1917 
and  1918  and  study  the  acreage  of  the  three  previous  years,  it  will 
be  noted  that  there  is  comparatively  little  fluctuation  in  the  total 
acreage  planted.  On  the  other  hand,  it  is  at  once  apparent  from 
the  data  presented  that  there  is  comparatively  little  relation  between 
acreage  and  yield.  This  statement  can,  perhaps,  be  best  illus- 
trated by  noting  the  variation  in  yield  between  Iowa's  1915  and 

1916  crops,  in  which  the  acreage  variation  is  less  than  5  per  cent., 
while  that  of  the  yield  is  nearly  160  per  cent.  Further  evidence  of 
fluctuating  variations  in  yield  may  be  noted  by  a  comparison  of 
the  New  York,  Michigan,  and  Wisconsin  data,  in  which  the  varia- 
tion in  acreage  between  the  years  1915  and  1919  in  New  York 
was  less  than  3.3  per  cent,  while  the  variation  in  yield  was  nearly 
80  per  cent.  The  Michigan  data  show  the  widest  variation  in 
yield  between  the  years  1916  and  1917  in  which  the  acreage  fluc- 
tuation was  a  little  over  1.8  per  cent  while  the  yield  variation  was 
nearly  134  per  cent.     In   Wisconsin,  the  variation  in   1916  and 

1917  potato  acreage  was  a  little  less  than  6  per  cent,  while  the 
increase  in  yield  was  nearly  157  per  cent. 

The  chief  interest  in  these  data  lies  not  so  much  in  the  magni- 
tude of  production  of  each  state,  as  it  does  in  the  average  yield 
per  acre.  This,  it  would  seem,  is  a  better  indication  of  the  relative 
adaptability  and  economic  value  of  a  crop,  than  is  that  of  its 
magnitude  of  production  in  any  given  state.  Considered  on  this 
basis,  Maine  leads  with  187.1  bushels  per  acre;  Nevada,  second, 
with  183.1;  Utah,  third,  with  164.4;  and  Idaho  fourth, 
with  154-1  bushels.  In  each  of  these  states  except  the  first,  most  of 
the  potatoes  are  grown  on  irrigated  land.  The  lowest  yielding 
states  are  those  of  Texas,  Oklahoma,  Louisiana,  Kansas,  and 
Georgia.  In  most  of  these  states,  potatoes  are  grown  largely  for 
the  early  market;  consequently  they  are  usually  harvested  before 
they  have  attained  their  full  growth,  and  in  consequence  thereof, 
do  not  give  the  yields  that  they  otherwise  would  if  allowed  to 
reach  full  maturity. 


A  SUMMARY  11 

Potato  Production  in  Canada. — While  the  production  of  pota- 
toes in  Canada  has  not  assumed  the  magnitude  of  that  of  the 
United  States  as  judged  in  terms  of  bushels,  it  more  than  compares 
favorably  with  it,  if  the  comparison  is  made  on  the  basis  of  popula- 
tion. On  such  a  basis,  the  1918  Canadian  crop  of  105,579,000 
bushels  would  call  for  a  production  by  the  United  States  of  about 
1,302,141,000  or  nearly  four  times  as  much  as  is  now  being  grown. 
It  will  be  seen,  therefore,  that  much  depends  upon  the  kind  of 
comparison  that  one  attempts  to  make,  as  to  whether  a  crop  seems 
relatively  small  or  relatively  large.  iVll  of  the  nine  provinces  which 
constitute  the  Dominion  of  Canada  produce  considerable  quantities 
of  potatoes  as  compared  with  their  population.  For  the  purpose 
of  comparison,  the  acreage,  production  and  average  price  per  bushel 
for  the  years  1913  to  1918  have  been  tabulated  (see  Appendix). 
A  study  of  this  data  shows  quite  a  variation  in  yields  from  year 
to  year  which,  for  the  most  part,  are  attributable  to  unfavorable 
or  favorable  climatic  influences. 

Total  Production  and  Yield  per  Acre  hy  Provinces. — A 
further  study  of  the  data  shows  that  they  stand  in  production  in 
the  following  order,  the  total  average  production  being  given : 

Quebec    2 1,076, .571  bushels,  144. .5  bush,  per  acre. 

Ontario     18,352,286  bushels,  120.1  bush,  per  acre. 

New    Brunswick     8,278,514  bushels,   186.2  bush,  per  acre. 

Nova  Scotia    7,255,786  bushels,  199.7  bush,  per  acre. 

Saskatchewan   6,211,843  bushels,  154.3  bush,  per  acre. 

Prince    Edward    Island    5,885,329  bushels,  182.7  bush,  per  acre. 

Manitoba     4,893,556  bushels,  159.6  bush,  per  acre. 

Alberta     4,891,914  bushels,  157.9  bush,  per  acre. 

British   Columbia    3,221,857  bushels,  207.6  bush,  per  acre. 

The  data  on  the  production  of  Canada  for  the  years  1913  to 
1918,  as  shown  in  the  table,  indicate  the  same  variation  in  yields 
as  in  the  United  States,  with  the  additional  feature  of  a  very  large 
increase  both  in  acreage  and  production  in  1918. 

Acreage  and  Yields  hy  Years. — The  next  table  shows  the 
results  arranged  by  years  from  1913  to  1918  inclusive.  * 

A  Summary  of  the  data  relative  to  production  indicates  that 
the  total  average  yield  for  the  United  States  and  Canada,  exclusive 
of  Newfoundland,  for  the  past  five  seasons,  1914  to  1918  inclusive, 
is  459,169,740  bushels.  If  we  add  to  this  about  one  and  one-half 
million  bushels  from  Newfoundland  and  a  million  bushels  from 
Mexico,  it  makes  the  average  total  production  of  North  America 

*Data  taken  from  Canada  Census  and  Statistic  monthly. 


12  POTATO  PRODUCTION  IN  NORTH  AMERICA 

ai)])roximately  461,()fi!),740  bushels  or  a  little  over  one-fourtli  that 
of  Germany.  If,  on  the  other  hand,  we  regard  the  last  two  seasons' 
crops  as  more  nearly  indicative  of  what  can  be  marketed  advanta- 
geously in  the  North  American  continent,  we  need  to  add  about  fifty 
million  more  bushels  to  the  figures  previously  submitted,  making 
a  grand  total  of  over  510  and  one-half  million  bushels. 

Total  acreage  and  production  of  potatoes  in  Canada  for  the  years  1912-1!) IS 


Year 

A.creage 

Total 

Av.  bus. 

Av.  price 

Yield  bus. 

per  acre. 

per  bus. 

1912 

484,000 

84,885.000 

175.4 

$0.44 

1913 

473.500 

78,544,000 

165.9 

.49 

1914 

475,900 

85,672,000 

180.0 

.49 

1915 

479,000 

02,604,000 

130.8 

.57 

1916 

473,000 

63,297.000 

136.2 

.81 

1917 

656,958 

79,892,000 

121.5 

1.01 

1918 

735,192 

105,579,700 

143.5 

.98 

Average 

539,650 

80,067,671 

150.5 

.684 

One  of  the  most  significant  features  of  potato  production  in 
the  United  States  is  that,  during  the  past  five  seasons  1915-1919, 
the  21  Northern  States  produced  over  two-thirds  (68.8  per  cent) 
of  the  total  crop,  the  remaining  third  being  about  equally  divided 
between  the  11  Far  West  States  and  the  16  Southern  States. 

United   States   Crop,   370,493,800   bushels. 
21  Northern  States       258,006,200  bushels,  68.8  per  cent. 
11    Far    West    States      56,238.200  bushels,  15.2  per  cent. 
16  Southern  States         56,249,400  bushels,   16.0  per  cent. 

As  larger  areas  in  the  far  west  states  are  brought  under 
irrigation,  increased  potato  production  may  be  expected,  but  the 
l)ulk  of  the  crop  must,  of  necessity,  be  produced  -within  a  reasonable 
distance  of  the  consuming  public. 

QUESTIONS    ON    THE   TEXT 

1.  Of  what   importance   is  the  potato  as  an   aj^rieultural   crop   in  North 

America  ? 

2.  According  to  the  data  presented,  what  states  lead  in  potato  production? 

3.  Does  the  second  period  of  live  years  show  any  material  change  in  the 

relative  rank  of  the  leading  .states? 

4.  What  two  factors  influence  potato  production  in  any  given  section? 

5.  Which  of  the  two  factors  is  the  greater? 

6.  What  lessons  are  to  be  derived  from  the  average  yields  per  acre  for 

the  difi'erent  states? 

7.  Name  some  of  the  highest  yielding  states? 


QUESTIONS  SUGGESTED  BY  THE  TEXT  13 

8.  Name  some  of  the  lowest  yielding  ones? 

9.  How  does  the  Canadian  crop  compare  in  per  capita  production  with 

that  of  the  United  States? 

10.  Which  of  the  nine  Canadian  provinces  shows  the  largest  average  acre 

production? 

11.  How  does  the  acreage  production  of  the  provinces  compare  with  that 

of  individual  states  in  the  United  States? 

12.  \\]mt  is  the  approximate  extent  of  the  North  American  potato  crop? 

13.  How  does  it  compare  with  that  of  Germany? 

14.  What  percentage  of  the  potato  crop  of  the  United   States  do  the  21 

Northern  States  produce? 

15.  How  much  do  the   11   Western  States  produce? 

16.  How  much  do  the  16  Southern  States  produce? 

17.  What  limits  a  large  expansion  of  potato  production  in  the  West? 

QUESTIONS  SUGGESTED  BY  THE  TEXT 

1.  Have   the   yields   and   acreages   in   your   state   been   increasing   or  de- 

creasing ? 

2.  Give  the  probable   factors  influencing  this. 

3.  Are  the  yields  per  acre  in  your  state  changing  materially?     If  so,  why? 

4.  Compare    the   yields    of   potatoes   in   your    state   with    six   other    food 

crops  of  the  state. 

5.  Compare  the  potato  production  in  your  state  with  other  states  nearest 

to  it  in  rank. 


CHAPTEK  III 

LEADING  ENVIRONMENTAL  INFLUENCES  IN 

POTATO  CULTURE.— SOIL,  TEMPERATURE, 

AND  MOISTURE 

The  three  leading  environmental  influences  which  are  most 
closely  associated  with  the  ])roduction  of  a  profitable  crop  of  pota- 
toes are  those  of  soil,  temperature,  and  moisture.  These  factors, 
while  not  so  completely  under  the  control  of  the  grower  as  those 
of  plant  food,  tillage,  and  spraying,  are,  nevertheless,  under  intelli- 
gent management  capable  of  a  considerable  degree  of  modification. 

The  first  requisite  on  the  part  of  the  grower  in  the  profitable 
production  of  any  crop  is  a  thorough  understanding  of  its  require- 
ments in  the  way  of  soil,  temperature,  and  moisture.  It  is  neces- 
sary to  know  whether  it  is  a  heat  or  a  cold,  a  moisture  or  a  drought 
loving  plant,  and  the  character  of  soil  best  suited  to  its  develop- 
ment. In  the  case  of  the  potato,  it  is  well  known  that  it  is  a  cool 
loving  plant;  that  it  requires  a  reasonable  supply  of  moisture  for 
its  best  development,  and  that,  while  more  or  less  cosmopolitan  in 
its  soil  requirements,  it  nevertheless  thrives  best  on  sandy,  gravelly, 
or  shaly  loam  soils. 

The  successful  production  of  potatoes  may  then  be  said  to  be 
confined  to  regions  in  which  the  mean  temperature  during  the 
growing  season  is  relatively  low;  where  the  normal  rainfall  during 
the  same  ])eriod  is  sufficient  to  insure  a  steady  growth  of  the 
plants,  or  where  the  land  can  be  irrigated  and  where  the  soil  is  of 
such  a  character  as  to  provide  the  most  suitable  conditions  for  the 
development  of  both  plants  and  tubers.  To  a  certain  extent, 
therefore,  these  requirements  confine  the  production  of  the  late 
potatoes,  at  least,  to  the  northern  portions  of  the  United  States. 

Soil  Requirements. — While  the  potato  plant  is  rather  cos- 
mopolitan in  its  soil  requirements,  it  nevertheless  succeeds  much 
better  on  certain  types  of  soils  than  on  others.  Generally  speaking, 
sandy,  gravelly  or  shaly  loam  soils  are  conceded  to  be  the  best, 
while  a  heavy  sticky  clay,  or  a  very  light  sandy  soil  is  admittedly  the 
poorest  and  should  always  be  avoided  when  possible.  Potatoes  may 
be  successfully  grown  on  muck  or  peat  soils,  and  in  certain  sections 
of  the  United  States  quite  a  potato  industry  has  been  developed 
on  these  types  of  soil.  As  a  rule,  however,  potatoes  produced  on 
14 


TEMPERATURE  CONDITIONS  15 

muck  or  peat  soils  are  less  rich  in  starch  than  those  grown  on  a 
gravelly  or  sandy  loam  soil.  To  be  entirely  suited  to  the  potato 
crop  a  soil  must  be  loose  and  friable,  well  supplied  with  organic 
matter,  deep,  well  drained  and  with  sufficient  moisture,  either  from 
natural  or  artificial  sources,  to  insure  the  development  of  a  good 
crop.  Furthermore,  as  is  shown  in  the  discussion  of  temperature, 
soil  which  is  naturally  cool  is  the  more  desirable  for  potato  culture. 
The  type  of  soil  known  as  the  Caribou  loam,  which  is  found  in 
Aroostook  County,  Maine,  is  almost  ideal  in  this  respect.  This 
is  a  chocolate  brown  colored  soil,  abundantly  supplied  with  -small 
decomposing  fragments  of  shale  rock  with  which  it  is  underlaid. 
This  shale  formation,  which  generally  lies  in  a  vertical  or  partially 
horizontal  position,  is  more  or  less  regularly  seamed,  affording 
almost^  perfect  drainage  through  its  crevices,  while  during  dry 
weather  it  serves  as  a  source  of  moisture  supply  to  the  soil  above  it. 

The  question  of  soil  moisture  is  not  such  a  vital  one  in  the 
irrigated  regions  of  the  West,  as  is  the  question  of  drainage  and 
suitability  of  the  physical  texture  and  composition  of  the  soil  to 
the  potato  plant  and  to  irrigation. 

Land  Elevation. — The  elevation  of  the  land  may  and  does 
very  materially  influence  its  desirability.  The  choice  of  simi- 
larly located  lands  with  respect  to  shipping  facilities  should  always 
be  made  in  favor  of  that  having  the  greatest  altitude,  provided 
such  altitude  is  not  sufficient  to  preclude  the  successful  growth 
of  the  potato.  For  example  in  the  New  England  States,  an  eleva- 
tion of  2000  to  2500  feet  is  equal  to  one  of  6000  or  7000  feet  in  the 
West,  so  far  as  seasonal  and  climatic  conditions  are  concerned, 
and  this  must,  of  necessity,  be  taken  into  consideration  in  the 
selection  of  a  potato  farm. 

Temperature  Conditions. — In  view  of  the  fact  that  tempera- 
ture plays  a  very  important  role  in  potato  production,  and 
that  it  is  a  factor  over  which  the  grower  can  exercise  very 
little  control,  it  is  essential  that  the  temperature  conditions  of 
any  given  locality  should  he  very  carefully  studied  before  engaging 
very  extensively  in  the  growing  of  this  crop.  In  this  connection, 
Smith^  says : 

"In  the  United  States  the  potato  has  made  its  greatest  development 
in  the  cooler  sections  of  the  country,  where  the  mean  annual  temperature 
is  between  40  and  50  degrees  F.  and  where  the  mean  temperature  in  July 
is  not  over  70  degrees.  Further,  the  greatest  yields  of  potatoes  per  acre 
are  in  those  states  where  the  mean  annual  temperature  is  be^ow  45,  and 
where  the  mean  of  the  warmest  month  is  not  far  from  65." 


IG  INFLUENCES  IN  POTATO  CULTURE 

He  further  assumes  the  thermal  constant  of  the  potato  to  be  43 
degrees  F.  and  that  the  sum  of  the  average  daily  degrees  of  lieat 
above  43  represents  the  effective  growing  temperature  for  tliis  crop 
iiecessary  to  bring  it  to  maturity. 

In  Ohio,  Smith  found  that  while  cool  weather  is  more  favorable 
to  tuber  production  than  warm,  in  each  month  considered,  the 
temperature  of  either  May,  June,  August,  September,  or  October 
alone,  has  very  sliglit  influence  as  compared  with  July  upon  the 


Fio.  3. — Environmental  influence  on  form  of  tuber  of  Green  Mountain.  Tubers  1,  2, 
5,  and  6,  very  much  modified;  3  and  4  true  to  type.  Modification  due  to  heat  and 
drouth.     Tubera  produced  from  the  same  strain  of  seed. 

potato  yield.  Also  that  the  temperature  of  June,  and  July,  July 
and  August,  or  June,  July  and  August  combined  had  just  about 
the  same  effect  as  that  for  July  alone.  It  is  believed  that  Smith's 
statement  should  be  qualified  by  a  further  one,  in  which  it  is  clearly 
set  forth  that  if  the  potato  crop  is  planted  in  Ohio  approximately 
at  a  given  date,  the  critical  temperature  period  in  the  gro\\'th  of 
the  plants,  so  far  as  its  influence  upon  yield  is  concerned,  is  during 
the  month  of  July.  The  critical  temperature  period  in  the  growth 
of  the  potato  plant,  insofar  as  it  exercises  a  distinctly  favorable 
or  unfavorable  influence  on  yield,  is  during  the  time  in  which  it 
is  developing  its  tubers.  In  regions  in  which  the  growing  season 
is  sufficiently  long  so  that  the  planting  date  may  vary  from  four 
to  six  or  more  weeks,  it  is  quite  possible,  with  a  thorough  knowledge 
of  the  average  normal  temperature  conditions  that  may  be  expected 
in  each  growing  month,  to  so  govern  the  time  of  planting  as  to 
subject  the  plants  to  the  most  unfavorable  temperature  conditions 
at  the  period  in   their  growth  when  the   least   injury   would   be 


TEMPERATURE  CONDITIONS  17 

incurred.  For  exam])le,  in  Western  New  York  it  is  customary  to 
delay  the  planting  of  the  late  croj)  of  j^otatoes  until  the  early  j)art 
of  June,  and  sometimes  even  to  July  1.  This  practice  is,  in  all 
I)robability,  not  the  direct  result  of  any  careful  study  of  the 
temperature  conditions  prevailing  in  any  given  month,  but  due 
rather  to  the  fact  that  the  later  planting  usually  gave  better  yields. 
A  four  years'  experience  in  growing  potatoes  near  Eochester,  New 
York,  inclines  the  writer  to  believe  that  August,  rather  than  July, 


Fig.  4. — Enviroiiineiital  iiiflucuce  on  form  of  tuber  of  Irish  Cobbler.  Tubers  1  and  2 
very  much  modified,  3  and  4  true  to  type.  Modification  dvie  to  heat  and  drought.  Sources 
of  seed  identical. 

is  the  critical  month  in  that  section;  August  rather  than  July  be- 
ing the  critical  month  simply  from  the  fact  that  the  crop  is 
])lanted  later,  and  is  setting  its  tubers  during  this  period.  Were 
the  crop  planted  a  month  earlier,  July  would  doubtless  represent 
the  critical  period.  There  can  be  no  question  but  that  high  air 
and  soil  temperatures  are  incompatible  with  a  healthy  and  normal 
growth  of  the  potato  plant;  and  if  extremely  high  temperatures 
prevail  when  the  plants  should  normally  set  and  develop  their 
tubers,  the  yield  will  be  materially  reduced  and  the  tubers  visibly 
modified  (Figs.  3-6).  For  this  reason,  the  chief  potato  producing 
regions  of  the  United  States  must,  of  necessit}-,  be  confined  to 
the  northern  and  north-eastern  tier  of  states.  In  the  South  where 
the  potato  is,  in  some  sections,  grown  extensively  as  an  early  truck 
crop,  early  planting  provides  temperature  conditions  which  in  the 
main  are  comparable  v/ith  those  of  the  North.  In  this  connection 
Smith  says  (p.  224)  "that  whether  the  date  of  planting  is  February 
2 


18 


INFLUENCES  IN  POTATO  CULTURE 


in  northern  Georgia,  or  May  1  in  the  northern  })ortion  of  the 
United  States,  the  seasonal  rise  has  brought  the  temperature  close 
to  45  degrees  F." 

It  should  be  clearly  borne  in  mind  that  while  the  amount  of 
injury  sustained  ])y  the  potato  plant  is,  as  has  been  said,  very 
largely  dependent  on  whether  it  occurs  during  the  critical  period 
in  the  development  of  the  plant,  there  is  another  element  Avhich 
may  very  materially  increase  or  minimize  high  temperature  injury 


Ficj.  5. — Enviroiiiiieiital  influence  on  form  of  tuber  of  Carman  No.  3  Tubers  1  anil  2 
very  much  modified,  3  and  4  true  to  type.  Modification  due  to  heat  and  drought.  Source 
of  seed  identical. 

to  the  crop,  and  that  is  the  presence  or  absence  of  a  sufficient 
amount  of  moisture  in  the  soil.  If  high  temperatures  are  accom- 
panied by  a  low  soil  moisture  content  during  the  critical  period 
in  the  life  of  the  plant,  and  these  conditions  prevail  for  any  con- 
siderable period,  the  injury  sustained  will  be  very  much  greater 
than  when  a  sufficient  amount  of  soil  moisture  is  present.  In  the 
first  place,  high  temperatures  accompanied  by  a  drought  usually 
result  in  a  large  amount  of  what  the  physiologist  recognizes  as 
tip-burn  of  the  foliage,  brought  about  through  a  more  rapid  trans- 
piration of  moisture  through  the  leaves  of  the  potato  plant  than 
its  roots  can  supply,  owing  to  lack  of  available  moisture  in  the  soil. 
As  a  result  of  this  unbalanced  ratio  between  moisture  loss  and 
moisture  supply,  the  cells  of  the  tips  and  margins  of  the  growing 
leaves  soon  collapse  and  dry  up,  giving  the  ]ilant  the  appearance 
of  having  been  scorched  by  fire.     This  type  of  injury  may  occur 


SOIL  TEMPERATURES  19 

prior  to  the  formation  of  tubers,  but  is  far  more  likely  to  occur 
during  or  after  their  formation. 

The  presence  of  a  sufficient  amount  of  soil  moisture  exercises 
a  favorable  influence  on  the  soil  temperature  during  protracted 
heat  periods,  by  reason  of  the  cooling  effect  exerted  through  the 
evaporation  of  moisture  from  both  the  soil  and  the  plants  grow- 
ing thereon. 

Soil    temperatures    are    believed    to    play    a    by    no    means 


Fig.  6. — Environmental  influence  on  form  of  tuber  of  Rural  New  Yorker  No.  2.  Tubers 
1  and  2  very  much  modified,  3  and  4  true  to  type.  Modification  due  to  heat  and  drouth. 
Source  of  seed  identical. 

unimportant  role  in  the  determination  of  potato  yields.  Of 
course,  it  must  be  conceded  that  high  soil  temperatures  cannot 
obtain  except  when  a  high  air  temperature  prevails.  In  some 
greenhouse  studies  recently  made  by  Pitch^  the  effect  of  tempera- 
ture and  moisture  upon  the  health  and  vigor  of  potato  plants  was 
noted.  The  soil  temperatures  employed  were  50,  65,  80,  and 
90  degrees  F.,  and  the  moisture  content  of  the  soil  approximately 
10  to  20  per  cent  for  all  the  period;  20  per  cent  for  75  days,  then 
30  for  5  days ;  and  40  for  the  fourth  lot,  which,  however,  the  author 
says,  he  did  not  dare  to  use  during  the  main  growing  period,  be- 
lieving that  it  would  cripple  the  plants.  Potatoes  maintained  at 
95  degrees  F.  were  all  killed  before  coming  up. 

In  regard  to  the  relation  of  temperature  to  moisture  Fitch 
found  a  distinct  correlation,  that  is,  the  higher  the  temperature 
and  the  moisture  the  greater  the  amount  of  injury  to  the  plant. 
Plants  grown  in  soil  having  an  approximate  moisture  content  of 
10  per  cent  did  not  show  any  bad  effects  from  being  subjected 
to  80  degrees  F. 


20  INFLUENCES  IN  POTATO  CULTURE 

Moisture. — The  important  rule  that  water  plays  in  the  gro^^i;h 
of  both  plants  and  animals  has  long  been  recognized  and  has  very 
justly  received  a  great  deal  of  attention.  Several  years  ago  Arthur  ^ 
road  a  paper  before  the  memliers  of  the  American  Carnation 
Society,  entitled  "Moisture,  the  Plant's  Greatest  Requirement"  in 
which  the  following  statements  were  made  (p.  67)  : 

"If  we  remembei-  that  the  chief  growth  of  the  plant  takes  place  in  the 
parts  where  the  largest  amount  of  water  occurs,  we  shall  be  reasonably 
safe  in  inferring  that  'water  is  a  very  essential  factor  in  growth.  It  has 
been  ascertained,  in  fact,  that  the  tissues  must  not  only  be  saturated  with 
water,  but  they  must  be  super-saturated,  that  is,  contain  so  much  water 
that  every  cell  is  distended  with  the  pressure,  before  growth  will  proceed." 

It  is  well  known  that  the  food  elements  in  the  soil  necessary  to 
the  proper  development  of  the  plant  must  first  be  brought  into 
solution  by  tlie  soil  moisture  before  they  can  be  taken  up  by  the 
delicate  root-hairs  of  the  j^lant.  Furthermore,  it  is  known  that 
water  is,  also,  just  as  essential  in  transporting  the  liquefied  food 
elements  from  root  to  leaf,  and  the  elaborated  food  from  the  leaves 
to  other  parts  of  the  plant.  Hence  it  is  that  every  metabolic  pro- 
cess of  the  plant  is  concerned  with  moisture.  At  the  same  time,  it 
must  be  remembered  that  while  an  abundance  of  water  is  desiralile, 
an  over-abundance  may  be,  and  usually  is,  harmful. 

Moisture  Bequirements. — The  actual  amount  of  water  neces- 
sary to  the  development  of  one  pound  of  dry  matter  in  the  growing 
plant  has  been  rather  carefully  studied  by  the  plant  physicist.  King* 
of  Wisconsin,  found  that  it  required  from  301  to  576  pounds  of 
water  to  produce  one  pound  of  dried  potato.  Briggs  and  Shantz" 
found  that  it  required,  nnder  semi-arid  conditions  in  Colorado,  636 
l)Ounds  of  water  to  produce  one  pound  of  dry  matter.  Widtsoe*'  in 
a  somewhat  different  manner  ascertained  that,  under  irrigation 
conditions  as  they  obtain  in  Utah,  the  evapo-transpiration  ratio 
between  moisture  and  dry  matter  varied  in  direct  ])roportion  to  the 
number  of  acre  inches  of  Avater  applied  to  the  crop.  When  5  acre 
inches  were  applied,  the  ratio  was  1  to  1136;  while  with  60  acre 
inches  it  was  1  to  3292. 

Usually  measurements  of  water  required  to  produce  one  pound 
.  of  dry  matter  are  based  upon  the  amount  of  water  actually  tran- 
spired by  the  leaves  and  stems  of  the  plant  and  do  not  therefore 
represent  the  moisture  loss  due  to  evaporation  from  the  soil  itself 
Smith  says,  {I.e.  p.  225)  : 


RAINFALL  21 

"This  water  requirement  is  sometimes  called  the  'transpiration  ratio' 

It  does  not  take  into  account  the  water  from  !a  rainfall  that  may  run 

off  from  the  surface  of   the  ground   or   what   is   lost  by   seepage  or  sur- 
face evaporation." 

Widtsoe's  data  takes  both  of  these  factors  into  consideration. 

RainfalL — In  determining  the  suitability  of  any  given  region 
for  potato  production  on  the  basis  of  annual  rainfall  it  is  highly 
essential  that  careful  consideration  should  be  given  to  the  distri- 
bution of  the  season's  rainfall.  The  average  precipitation  during 
the  growing  season  is  the  real  determining  factor.  In  the  best 
potato  growing  regions  the  average  total  rainfall,  during  the 
period  between  planting  and  harvesting  late  potatoes,  varies  from 
12  to  nearly  18  inches.  But,  even  where  the  heavier  precipitation 
occurs,  it  might  be  so  unevenly  distributed  as  to  make  it  impossible 
to  produce  heavy  yields.  A  goodly  supply  of  moisture  is  essential 
to  a  quick  and  healthy  growth  of  the  plant,  and,  when  the  tubers 
are  set,  to  promote  a  steady  and  uniform  gro^vth.  Heavy  pre- 
cipitations during  the  latter  part  of  the  growing  season  are  not 
desirable,  as  they  favor  the  development  of  late  blight  and  rot, 
and  also  make  it  difficult  to  harvest  the  crop  in  a  satisfactory 
condition.  Much  may  be  done  by  the  grower  to  conserve  the  soil 
moisture  by  good  cultivation  and  the  maintaining  of  an  earth 
mulch.     This  subject  will  l)e  more  fully  discussed  under  tillage. 

QUESTIONS   ON   THE   TEXT 

1.  What  are  the  three  leading  environmental  factors  in  potato   culture? 

2.  To  what  extent  are  these  three  factors  controllable  by  man? 

3.  To    what    regions    is    the    successful    production    of    potatoes    usually 

confined  ? 

4.  What  are  the  soil  requirements  for  potatoes? 

5.  Describe  the  Caribou  loam  soil. 

6.  Of  what   importance  is   land   elevation? 

7.  What  does  Smith  say  about  temperature  influence? 

8.  According  to  Smith,  which  is  the  most  critical  period  in  the  life  of 

the  potato  plant  so  far  as  tuber  production  is  concerned? 
fl.  If  any,  what  qualification  would  you  make? 

10.  What  happens  to  the  potato  plant  when  high  air  and  soil  temperatures 

are  accompanied  by  a  low  soil  moisture  content? 

11.  Explain  physiological  collapse  of  cell  structure  of  the  leaf? 

12.  What    eft'ect    has    high    soil   temperature   on   tuber    production?     Cite 

Fitch's  experiments. 
1.3.  Of  what  importance  is  moisture  to  the  plant? 

14.  Give  Arthur's  statement  regarding  cell  saturation  and  cell  growth, 
l.'i.  What  amount  of  water  did   King,   Briggs,   Shantz,   and   Widtsoe   find 

was  necessary  to  produce  a  pound  of  dry  matter? 
16.  In  determining  the  suitability  of  any  given  region  to  potato  production 

based  on  its  rainfall,  what  factors  should  be  considered? 


22  INFLUENCES  IN  POTATO  CULTURE 

QUESTIONS   SUGGESTED  BY  THE  TEXT 

1.  To   what   extent    is    the   soil   of    your    region    considered    suitable    fur 

potato  growing? 

2.  What  bad  effects  of  summer  heat  are  noticed  Ijy  your  local  growers? 

3.  In  what  months,   if  any,   is   the   local   rainfall   "likely   to   be  deficient? 

4.  Find   specimens,   if   possible,   showing   results   similar   to   those   shown 

in  the  figures  of  this  chapter. 

References   Cited 

1.  Arthue,    J.    C.      1898.      ]VI|0isture,    the    plant's    greatest    requirement. 

I'roc.  tSeventh  Ann.  Meeting  Am.   Carnation  Soc:    65-70,   Feb.    1898. 

2.  Briggs,  L.  J.  and  H.  L.  Shantz.     1914.     Relative  water  requirements 

of  plants,     v.  ti.  Dept.  Agr.  Jour.  Agr.  lies.  3:   1-04,  7  pis.  2  figs.  1914. 

3.  Fitch,   C.   L.     1915.     Studies   of   health   in  potatoes.     Col.   <S'ia.   Bui. 

216:16.  21,  Nov.   1915. 

4.  King,  F.  H.     1897.     Soil  Management.     216:217,1914.     Also  Wis.  Sta. 

Rpt.   1897:    228-230. 

5.  Smith,  VV.   J.     1915.     The   effect  of   the   weather   upon   the  yield   of 
potatoes.     U.  8.  Dept.  Agr.  Mo.  Weather  Review,  May,  1915:   222-228. 

0.  Widtsoe,  J.  A.     1912.     The  effect  of  irrigation  on  dry  matter.     Utah 
8ta.  Bui.  116:57,  Sept.  1912. 


CHAPTEE  IV 
THE  SOIL  AND  ITS  PREPARATION  FOR  THE  CROP 

In  the  preceding  chapter  the  question  of  soil  was  discussed, 
as  an  environmental  factor  exercising  a  more  or  less  direct  in- 
fluence on  the  character  of  the  potato  crop  produced.  In  the 
present  chapter  it  is  proposed  to  study  the  soil  from  the  standpoint 
of  its  proper  preparation  for  the  crop.  It  is  well  known  that  while 
the  potato  is  probably  as  cosmopolitan  in  its  soil  requirements 
as  almost  any  other  agricultural  crop,  it  nevertheless  thrives  best 
on  certain  types  of  loam  soil,  as  for  example  sandy,  gravelly  or 
shaly  loam  soils.  Maximum  crops  cannot  be  expected  from  very 
light  sandy,  or  heavy   clay   soils.     Neither   can  maximum   crops 


Fig.  7. — Plowing  a  clover  sod  with  a  tractor  turning  two  furrows  14  inches  in  width  and 
9  and  10  inches  in  depth.     Aroostook  Co.,  Me.,  Aug.,  1917. 

be  obtained  from  poorly  drained  soils,  or  from  those  deficient  in 
organic  matter,  or  in  plant  food.  Hence  all  these  points  should 
be  carefully  studied  before  selecting  the  soil  on  Avhich  the  crop  is 
to  be  grown. 

Organic  Matter. — The  importance  of  an  abundant  supply  of 
organic  matter  in  the  soil  can  hardly  be  over-emphasized.  A 
goodly  supply  of  organic  matter  not  only  permits  of  keeping  the 
land  in  a  much  more  friable  condition,  but  guarantees,  as  it  were,  a 
continuous  supply  of  available  plant  food.  In  view  of  the  relative 
importance  of  organic  matter,  or  humus,  as  it  is  commonly  called, 
in  the  soil,  it  is  always  desirable  to  grow  potatoes  on  a  clover  or 
alfalfa  sod  whenever  it  is  possible  to  do  so.     In  the  South  the 

23 


24  THE  SOIL  AND  ITS  PREPARATION 

(,u\vp(^a,  velvet  bean  or  the  soybean  may  serve  the  same  purpose, 
and  be  a  more  acceptable  plant  to  grow  in  tlie  crop  rotation.  As 
rotation  crops  are  discussed  in  another  chapter  it  is  unnecessary 
to  further  consider  this  matter  except  that  it  concerns  the  plowing 
under  of  the  rowen  in  the  fall  in  the  case  of  clover  in  the  North, 
or  of  the  last  cutting  of  alfalfa  in  alfalfa-growing  districts  or  of 
cowpeas,  velvet  beans,  or  soybeans  in  the  South. 

Plowing  and  Fitting  the  Land. — Tt  is  generally  dejiirable  to 
]>low  the  land  intended  for  the  potato  crop  in  the  fall,  except  in 


Fig.  8. — Plowing  a  clover  sod  with  a  pair  of  horses. 

the  case  of  soil  that  is  apt  to  wash  badly  during  the  winter  rains 
and  snows.  The  plowing  of  the  land  varies  somewhat  according 
to  whether  the  previous  crop  was  alfalfa  or  clover. 

Alfalfa  Sod. — The  usual  practice  in  handling  an  alfalfa  sod 
is  to  crown  it  early  in  the  autumn.  The  process  of  crowning  con- 
sists in  plowing  the  sod  as  lightly  as  possible,  three  to  four  inches 
is  sufficient,  and  allowing  it  to  lie  exposed  to  the  sun,  rain,  snow 
and  frost  during  the  winter  months.  The  object  of  early  crowning 
of  the  sod  is  to  furnish  favorable  conditions  for  the  drying  uj)  of 
the  crowns  of  tlie  plants.  This  process  is  materially  aided  by 
repeated  disking  of  the  crowned  land  in  the  autumn.  In  the  spring, 


CLOVER  SOD 


25 


this  land  should  be  plowed  to  a  depth  of  from  9  to  10  or  more 
inches.  The  above  method  for  preparing  alfalfa  land  for  a  potato 
crop  is  the  one  most  generally  practised,  but  there  are  a  few  growers 
who  prefer  spring  plowing,  after  the  alfalfa  has  attained  a  height 
of  from  8  to  12  inches.  When  this  practice  is  followed,  only  one 
plowing  is  made  and  this  one  as  deep  as  it  is  possible  to 
do  conveniently. 

Clover  Sod. — It  is  the  general  custom,  where  a  clover  sod  is 
to  be  turned  under,  to  plow  the  land  in  the  fall.     At  this  time  it  is 


^ _^^i 

KsAfe 

Fig.  9. — The  use  of  the  plank  drag  is  the  final  step  in  the  preparation  of  the  potato- seed 
bed.  Where  the  ground  is  a  Uttle  cloddy  or  the  surface  somewhat  uneven,  the  grower  will  be 
well  repaid  for  the  extra  labor  involved.      (Courtesy  of  Daniel  Dean,  Nichols,  N.  Y.) 

always  plowed  to  its  full  depth,  viz.,  8  to  10  or  more  inches,  depend- 
ing on  the  depth  of  the  surface  soil  and  the  character  of  the  sub-soil 
(Figs.  7-9).  A  good  rule  to  follow  is  that  of  turning  up  from  a 
half  inch  to  one  inch  of  sub-soil  at  each  plowing  when  the  surface 
soil  is  too  shallow.  In  regions  where  the  planting  is  delayed  until 
the  first  to  the  fifteenth  of  June,  and  on  lands  that  have  a  tendency 
to  wash,  it  may  be  desirable  as  in  the  special  case  of  alfalfa  sod,  to 
plow  as  late  in  the  spring  as  it  is  possible,  in  order  to  turn  under 
a  goodly  mass  of  the  succulent  leaves  and  stems  of  the  clover  plant. 
But  whether  plowing  is  done  in  the  fall  or  the  spring,  it  should  be 
thoroughly  done,  and  every  effort  should  be  made  to  conserve  the 
moisture.  Fall-plowed  land,  if  not  to  be  replowed  in  the  spring, 
should  be  disked  and  harrowed  as  early  as  possible  in  the  spring 


26  THE  SOIL  AND  ITS  PREPARATION 

and  then  kept  friable  until  the  crop  is  planted.     Spring-plowed 
land  should  be  disked  as  plowed  and  kept  mellow. 

Preparation  of  the  Seed  Bed. — No  expense  should  be  spared  in 
preparing  the  seed  bed.  Tlie  deeper  it  is  prepared  and  the  more 
finely  it  is  pulverized,  the  more  suitable  it  is  for  the  production 
of  a  large  yield.  The  choice  of  implements  in  fitting  the  land  is, 
to  some  extent,  a  matter  of  personal  preference.  A  heavy  sod,  if  it 
has  been  well  plowed,  can  probably  be  most  quickly  and  satis- 
factorily put  in  shape  for  the  crop  by  the  use  of  the  cutaway  disk 
followed  by  a  smoothing  harrow.  Some  prefer  the  plain  disk  to  the 
cutaway  while  still  others  like  the  Acme  harrow.  The  latter  harrow 
is  especially  valuable  on  a  sod  that  tears  up  badly,  as  this  imple- 
ment slices  rather  than  tears  the  sod  apart.  Get  the  land  in  as 
finely  divided  a  condition  as  possible,  as  it  is  much  easier  to  do  it 
before  planting  than  it  is  afterwards.  If  the  land  is  lumpy,  roll 
it  with  a  heavy  roller  or  clod-crusher  and  then  harrow  it,  or  else 
run  a  plank  drag  over  it  until  the  surface  is  smooth  (Fig.  9). 
The  old  adage  that  "  a  stitch  in  time  saves  nine ''  is  quite  applicable 
to  the  proper  preparation  of  the  land. 

QUESTIONS    ON    THE   TEXT 

1.  What  are  some  of  the  factors  to  be  considered  in  the  selection  of  a 

suitable  soil  for  potatoes? 

2.  Of  what  importance  is  humus  to  the  soil? 

3.  What  crop  should  precede  a  potato  crop? 

4.  When  should  the  land  be  plowed? 

5.  How  should  an  alfalfa  sod  be  handled? 

6.  How  would  you  handle  a  clover  sod? 

7.  Where  late   planting  is   practised   what   variation    in   the   plowing   of 

the  land  is  suggested? 

8.  What  are  the  determining  factors  as  to  fall  or  spring  plowing? 

9.  How   would   you   proceed   to   handle   fall-plowed    land    in   the    spring? 
10.  How  would  you  handle  spring-plowed   land? 

QUESTIONS  SUGGESTED  BY  THE  TEXT 

1.  What  types  of  soil  are  used  for  potato  growing  in  your  region? 

2.  What  soils  have  you  that  are  not  suitable  for  potato  growing?     Why? 

3.  What  crops  are  grown  preceding  potatoes  in  your  region? 

4.  What  is  the  chief  source  of  organic  matter  for  local  crops  of  potatoes? 

5.  How  is  the  soil  usually  prepared  by  local  growers? 

6.  Is  spring  plowing  or  fall  plowing  usually  practised  by  local  growers? 

Why  ? 


CHAPTER  V 

FOOD  REQUIREMENTS  OF  THE  POTATO  CROP 
AND  HOW  SUPPLIED 

A  well  balanced  and  ample  food  supply  is  important  in  the 
production  of  any  crop  if  profitable  yields  are  to  be  secured.  This 
is  particularly  true  with  respect  to  crops  requiring  a  considerable 
expenditure  of  money  and  labor  in  producing  and  marketing  them. 
The  problem  confronting  the  grower  is  that  of  supplying  the 
necessary  food  elements  for  the  production  of  a  maximum  crop 
with  the  least  expenditure  of  money  and  effort.  It  is,  therefore, 
essential  to  have  somewhat  definite  information  as  to  what  these 
food  requirements  actually  are,  if  they  are  to  be  intelli- 
gently supplied. 

Chemical  Elements  in  Plants. — Notwithstanding  the  fact 
tliat  there  are  a  great  many  thousands  of  different  kinds  of  plants 
growing  on  the  earth's  surface,  and  that  among  these  there  is 
a  great  diversity  in  form  and  in  color  of  foliage  and  flower,  com- 
j)aratively  few  chemical  elements  are  drawn  upon  to  produce  them. 
Of  the  eighty  or  more  known  chemical  elements  it  is  claimed  by 
the  chemist  that  only  fourteen  of  this  number  are  commonly  found 
in  plants.  These  fourteen  elements,  according  to  Van  Slyke^,  are 
calcium,  carbon,  chlorine,  hydrogen,  iron,  magnesium,  manganese, 
nitrogen,  oxygen,  phosphorus,  potassium,  silicon,  sodium  and  sul- 
pliur.  Fortunately  most  soils  are  sufficiently  well  supplied  with 
all  but  four  of  these  elements,  viz.  nitrogen,  phosphorus,  potassium 
and  calcium.  The  first  three  of  these  elements  are  generally  con- 
sidered the  essential  ones  as  calcium  is  more  generally  present  in 
soils  at  least  in  suffiicient  amount  for  the  plant's  needs  than  are 
the  other  three.  However,  there  are  many  soils  that  are  directly 
benefited,  so  far  as  their  crop  productive  power  is  concerned,  by 
an  application  of  calcium.  On  the  other  hand  not  all  soils  require 
nitrogen,  phosphorus  and  potash.  Take,  for  example,  the  soils  of 
the  Avestern  portion  of  the  United  States,  particularly  the  Inter- 
Mountain  section,  where  it  has  been  found  that  most  of  them  are 
generally  well  supplied  with  both  phosphorus  and  potash,  but  are 
wofully  deficient  in  nitrogen,  and  especially  in  organic  matter.  In 
still  other  sections  it  has  been  found  that  there  is,  for  the  present 
at  least,  a  sufficient  supply  of  nitrogen,  phosphorus  and  potash  to 

27 


28 


FOOD  REQUIREMENTS— HOW  SUPPLIED 


]»ro(luce  a  satisfactory  cTop.  Generally  speaking,  the  soils  of  the 
northeastern  portion  of  the  United  >States  are  benefited  by  an 
application  of  these  chemical  elements.  It  is  apparent,  therefore, 
that  one  must  study  his  own  soil  requirements  in  order  to  deter- 
mine whether  they  are  lacking  in  any  of  the  elements  mentioned. 
It  is  also  rather  essential  to  any  intelligent  application  of  plant 
food  to  know  what  amount  of  nitrogen,  phosphorus  and  potash 
a  200-bushel-acre  potato  crop  removes  from  the  soil. 

Relative  Amoimts  of  Nitrogen,  Phosphoric  Acid,  and  Potash  Removed  hy 
a  2f)f)-hitshcl-pcr-(icre  Crop  of  Potatoes. 


Source  of  data 

Nitrogen 

Phos- 
phoric 
Acid 

Potash 

Woods,  C.  D.  and  Bartlett,  J.  M.:  Main  Sta.  Bui.   r>7,   1899 

Van  Slyke,  L.  L.:  Fertilizers  and  Crops,  p.  163,  1915 

Voorhees    E    B  ■   Fertilizers  p  215   1903 

lbs. 
37.0 
42.0 
27.0 
54.0 
53.3 
42.66 

lbs. 
10.0 
18.0 
12.0 
20.4 
20.0 
17.28 

lbs. 
5S.0 
GO.O 
00.0 

Fraser  S    •  The  Potato   p   54    1905 

52.7 

Grubb.  E.  H.  and  Guilford,  W.  S.:  The  Potato,  p.,  211,  1912 
Average  amount  removed 

53.3 
56.8 

These  amounts  removed  could  be  supplied  with  about  270  pounds 
of  nitrate  of  soda,  108  pounds  of  a  16  per  cent  acid  phosphate,  and 
about  110  pounds  of  muriate  of  potash.  As  a  matter  of  fact, 
however,  it  is  necessary  to  apply  an  excess  of  plant  food  in  order 
to  make  good  the  losses  that  are  almost  certain  to  occur  through 
surface  washing,  leaching,  or  through  combination  with  inorganic 
substances  present  in  the  soil  which  may  result  in  the  formation 
of  an  insolul)le  compound.  In  any  case,  it  is  always  advisable 
to  supply  from  50  to  75  per  cent  more  plant  food  to  the  soil  than 
the  crop  is  likely  to  remove,  in  order  to  provide  for  the  various 
contingencies  mentioned. 

The  first  consideration  in  the  enrichment  of  a  soil  for  the 
production  of  potatoes,  after  one  has  a  thorough  knowledge  of 
its  requirements,  is  that  of  the  materials  available  for  this  ])urpose, 
their  cost,  and  their  economy  of  use.  Outside  of  the  mineral  ele- 
ments naturally  contained  in  all  soils  there  are  three  general 
sources  of  plant  food  of  wliich  the  grower  may  avail  himself  in  the 
enrichment  of  the  soil.  These  three  sources  are:  (1)  green 
manuring  or  the  turning  under  of  growing  crops,  (2)  farm 
manures,  (3)  commercial  fertilizers. 

Green  Manuring. — The  first  of  these  three  sources  of  plant 


GREEN  MANURING  29 

food  is  available  to  every  grower  who  is  willing  to  take  the  trouble 
of  growing  a  crop  to  be  turned  under.  Those  crops  which  are 
most  valuable  for  this  purpose  are  tlie  well  known  members  of  the 
pea  family,  or  legumes  as  they  are  more  generally  called.  The 
alfalfa,  clovers,  peas,  beans,  cowpeas,  soy  beans,  velvet  beans,  tre- 
foils, and  beggar  weeds  are  included  in  this  group.  Each  of  these 
members  has  its  own  peculiar  value  depending  on  the  soil  and  the 

Approximate  Amounts  of  Plant  Food  Constituents  in  one  Legume  Crop. 

Yield  per         Per  cent.  Phosphoric        Potash 

Crop  acre  lbs.  of  water  Nitrogen  Acid  (PiOs)         (K2O) 

green  mattei 


Alfalfa 

20,000 

75 

120  lbs. 

30  lbs. 

160  lbs. 

Clover,  alf^ike 

l(i,000 

82 

80  lbs. 

19  lbs. 

48  lbs. 

Clover,  crimson 

16,000 

82 

72  lbs. 

19  lbs. 

64  lbs. 

Clover,  mammoth 

20,000 

80 

100  lbs. 

24  lbs. 

80  lbs. 

Clover,   red 

12,000 

80 

66  lbs. 

16  lbs. 

60  lbs. 

Clover,  white 

8,000 

81 

40  lbs. 

16  lbs. 

24  lbs. 

Clover,  sweet 

20,000 

80 

110  lbs. 

30  lbs. 

100  lbs. 

Field  pea 

10,000 

82 

50  lbs. 

15  lbs. 

50  lbs. 

Cowpeas 

12,000 

84 

54  lbs. 

14  lbs. 

54  lbs. 

Soybean 

10,000 

1  -y 

50  lbs. 

15  lbs. 

60  lbs. 

Velvet  bean 

20,000 

7') 

110  lbs. 

30  lbs. 

110  lbs. 

Vetch 

10,000 

84 

50  lbs. 

10  lbs. 

45  lbs. 

climatic  conditions  under  which  it  must  be  grown.  Of  the  non- 
leguminous  plants,  rye,  crab-grass  and  buckwheat  are  probably  the 
most  commonly  employed. 

Considerable  humus  and  plant  food  is  added  to  the  soil  for  an 
ensuing  crop  by  simply  turning  under  a  good  grass  sod,  or  a  cow- 
pea,  soybean  or  velvet  bean  stubble,  but  it  does  not  compare  with 
that  added  when  the  whole  plant  is  turned  under.  The  question 
for  the  grower  to  decide  is  Avhether  it  is  more  profitable  to  harvest 
the  crop  for  hay,  with  the  idea  of  feeding  it  to  livestock  and  return- 
ing the  manure  to  the  land,  than  to  turn  it  all  under.  The  problem 
resolves  itself  into  whether  the  grower  has  the  livestock  to  which 
to  feed  the  crop ;  if  he  has  and  is  a  good  feeder  it  is  probably  more 
profitable  to  add  tlie  fertility  to  the  land  in  the  form  of  manure 
provided  the  manure  is  well  cared  for  prior  to  its  application  to 
the  soil.  Experiments  have  demonstrated  that  more  plant  food  is 
added  to  the  soil  when  the  crop  is  allowed  to  reach  a  fair  stage 
of  maturity  before  turning  it  under.  This  is  comparable  to  what 
has  been  learned,  regarding  the  best  stage  at  which  to  cut  silage 
corn  in  order  to  get  the  maximum  feeding  value  out  of  it. 


Phosphoric  Acid 

Potash 

14.0      Iha. 

54.0  lbs. 

45.95  lbs. 

101.9  lbs. 

18.8     lbs. 

54.8  lbs. 

33.0     lbs. 

155.0  lbs. 

30  FOOD  REQUIREMENTS— HOW  SXJPPLIED 

Van  Slyke  (I.e.  p.  556)  gives  the  following  data  relative  to 
the  average  fertilizing  constituents  in  various  leguminous  crops. 
A  comparision  of  this  data  on  cowpeas  as  presented  in  the  following 
table,  with  that  published  by  the  Alabama,-  New  Jersey,^  and  South 
Carolina*  stations  shows  a  rather  marked  difference  in  results  par- 
ticularly in  the  case  of  the  Alabama  and  South  Carolina  data. 

Whether  these  differences  were  due  to  heavier  yields  of  cowpeas 
or  to  variations  in  method  of  making  analysis  is  not  quite  clear. 
A  careful  study  of  the  data  as  a  whole,  cannot  fail  to  impress  the 
reader  with  the  importance  of  employing  leguminous  cover  crops 
in  regions  where  they  can  be  successfully  grown ;  or  in  using  clover 

Comparison  of  Cowpca  Analysis. 

Nitrogen 
Van   Slyke  54.0     lbs. 

Alabama   Station  123.27  lbs. 

New   Jersey   Station  74.8     lbs. 

South   Carolina   Station   205.0     lbs. 

Average  114.3     lbs.  27.9     lbs.  91.4  lbs. 

or  alfalfa  in  the  rotation  system  in  northern  sections  for  the  en- 
richment of  the  soil.  There  are  also  other  advantages  from  the  use 
of  green  manures,  or  even  in  turning  under  the  stubble  of  legum- 
inous crops,  quite  apart  from  their  fertilizing  elements.  The  two 
most  important  benefits  are  those  of  the  improvement  of  the  phys- 
ical character  of  the  soil  by  increasing  its  porosity,  and  at  the  same 
time  imparting  to  it  a  greater  water  holding  and  absorptive  capa- 
city. It  also  insures  greater  bacterial  activity  on  the  part  of  the 
soil  flora  particularly  of  the  nitrifying  organisms. 

Farm  Manures. — The  composition  of  farm  manures  is  ex- 
tremely variable,  because  it  is  entirely  dependent  upon  the  nature 
of  the  manure,  that  is,  whether  horse,  cow,  hog  or  sheep  manure, 
how  the  animals  were  fed  that  produced  it,  and  the  amount  of  care 
exercised  in  conserving  their  liquid  and  solid  excrement.  Van 
Slyke  {I.e.  p.  289)  gives  the  following  data  regarding  the  percent- 
ages of  plant  food  constituents  in  mixed  farm  manures.  Assuming 
the  average  analysis  to  fairly  represent  the  composition  of  a  reason- 
ably good  grade  of  farm,  manure,  the  application  of  ten  tons  per 
acre  would,  theoretically,  add  100  pounds  of  nitrogen,  50  pounds  of 
phosphoric  acid,  and  100  pounds  of  potash.     These  amounts  are 


CO*MMERCIAL  FERTILIZER  31 

largely  in  excess  of  the  plant  food  requirements  of  a  200-bushe] 
crop  of  potatoes. 

It  must  be  remembered,  however,  that  only  one-third  to  one- 
half  or  more  of  the  plant  food  elements  in  farm  manures  are 
available  to  the  crop  to  which  it  is  applied.  In  view,  therefore., 
of  the  rather  unbalanced  plant  food  constituents  of  farm  manure, 
that  is,  the  relatively  low  phosphoric  acid  and  high  nitrogen  content 
of  well  preserved  manures,  it  is  really  more  economical  to  supple- 
ment the  manure  with  a  commercial  fertilizer  rich  in  phosphoric 
acid  and  low  in  nitrogen.  An  application  of  ten  tons  of  manure 
per  acre  before  plowing  the  land  and  600  pounds  of  a  2-8-2  fer- 
tilizer, that  is,  2  per  cent  of  nitrogen,  8  per  cent  of  phosphoric 
acid,  and  2  per  cent  of  potash,  at  the  time  of  planting  should  give 

Composition  of  Farm  Manures. 


Nitrogen 

Phosphoric 

acid 

Po 

tash 

per  cent. 

lbs. 

per  cent. 

lbs. 

per  cent. 

lbs. 

Lowest 

analysis 

0.4 

S 

0.2 

4 

0.4 

8 

Hiohest 

analysis 

0.8 

10 

0.4 

8 

0.8 

16 

Average 

analysis 

0.5 

10 

.25 

5 

05 

10 

good  results.  This  would  add  12  pounds  each  of  nitrogen  and 
potash  and  48  pounds  of  phosphoric  acid  or  a  total,  including  that 
contained  in  the  ten  tons  of  manure,  of  112  pounds  of  nitrogen, 
98  pounds  of  phosphoric  acid,  and  112  pounds  of  potash.  While 
these  amounts  are  not  equal  in  phosphoric  acid  to  a  ton  application 
of  a  4-8-4  fertilizer,  they  contain  more  nitrogen  and  potash. 

Manure  Causing  Seal. — Where  entire  dependence  is  to  be 
placed  on  farm  manures  to  produce  a  crop  of  potatoes,  it  is  usually 
preferable  to  apply  the  manure  to  the  preceding  crop  or,  in  the  case 
of  clover,  after  the  first  crop  has  been  cut,  to  be  turned  under 
with  the  second  crop  of  clover  in  the  late  summer  or  early  autumn. 
This  is  advisable  in  order  to  avoid  danger  of  loss  from  common 
scab  infection,  which,  if  present  in  the  soil,  is  almost  certain  to 
cause  more  injury  to  the  potato  tubers  than  if  manure  were 
not  used. 

Commercial  Fertilizers. — The  use  of  commercial  fertilizers  in 
potato  production  is  an  almost  universal  practice  throughout  the 
Atlantic  Coastal  Plain  section  of  the  United  States  and  throughout 
the  greater  part  of  New  England.  They  are  not  used  extensively 
in  New  York  State  outside  of  Long  Island.     Their  use  is  by  no 


32  FOOD  REQUIREMENTS— HOW  SUPPLIED 

means  common  in  the  Middle  West  or  Northwest,  though  it  is 
probable  that  in  many  sections  they  could  be  employed  witli  profit. 
In  the  early  trucking  regions  in  the  South  the  growers  use  a  fer- 
tilizer containing  a  higher  percentage  of  nitrogen  than  those  in  the 
late  or  main  crop  localities.  This  is  primarily  due  to  the  fact  that 
they  are  desirous  of  forcing  a  quick  growth  of  the  plant  in  order 
to  hasten  the  harvesting  of  the  crop.  A  formula  used  rather  ex- 
tensively in  the  Norfolk  trucking  section  is  one  that  analyzes  7 
per  cent  ammonia,  5  per  cent  phosphoric  acid,  and  4  to  G  per  cent 
of  potash.  A  favorite  formula  at  the  present  time  in  .\roostook 
County,  Maine,  is  one  carrying  4  per  cent  ammonia,  8  per  cent 
pliosphoric  acid  and  4  per  cent  of  potash.  A  5-8-7  is  also  used 
quite  extensively.  When  Germany  placed  an  embargo  on  ])otash, 
the  Maine  potato  grower  was  using  a  fertilizer  containing  8  to 
10  per  cent  of  potash;  but  with  its  sharp  advance  in  price,  and  a 
very  limited  supply  on  hand,  the  fertilizer  manufacturer  found  it 
impossible  to  offer  goods  containing  over  5  per  cent  of  potash; 
and  only  a  very  limited  amount  containing  5  per  cent  potash  was 
obtainable  at  any  price.  A  large  percentage  of  the  fertilizers, 
offered  by  the  trade  in  1916,  contained  no  potash  whatever,  and  one 
of  the  favorite  no-potash  fertilizers  was  one  that  analyzed  5-10-0. 
It  was  thought  by  the  manufacturers,  as  well  as  the  growers,  that 
by  increasing  the  percentages  of  nitrogen  and  j^hosphoric  acid  it 
would  in  a  measure  overcome  the  lack  of  potash.  As  a  matter  of 
fact,  it  had  the  opposite  result  in  many  instances ;  it  had  a  tendency 
to  induce  an  unhealthy  condition  in  the  plant,  which,  on  the  Wash- 
burn loam  soils  of  Aroostook  County,  Maine,  soon  developed  well 
marked  cases  of  potash  starvation,  accompanied  by  the  premature 
death  of  the  plant.  There  is  every  indication  that  tubers  produced 
on  soil  so  deficient  in  available  potash  as  to  develop  well  marked 
cases  of  potash  starvation  in  the  growing  plants,  are  not  as  suitable 
for  seed  purposes  as  are  those  that  were  gro^vn  on  soil  in  which 
there  was  a  sufficipnt  sup])ly  of  this  element. 

Amount  of  Commercial  Fertilizer  to  Apply. — In  most  of  the 
Atlantic  Coastal  I'lain  region  the  truck  growers  use  all  the  way 
from  1500  to  2500  pounds  per  acre.  The  same  amounts  are  used 
in  Northern  Maine.  In  the  other  New  England  States  the  amount 
varies  rather  widely,  say  from  800  to  1800  ])ounds  with  an  occasional 
grower  using  a  ton.  In  Western  New  York  from  600  to  1200 
pounds  represent  the  average  range  of  applications  where  commer- 


COMMERCIAL  FERTILIZER 


33 


cial  fertilizers  are  used  at  all.  Tlie  same  statement  will  apply 
to  Michigan,  Wisconsin,  and  Miimesota.  The  use  of  commercial 
fertilizers  are  comparatively  unknown  west  of  the  Mississippi, 
except  in  the  southwestern  states  such  as  Louisiana,  Texas,  and 
Oklahoma.  In  these  states  cotton  seed  meal  has  been  the  chief 
source  of  nitrog'en. 


Fig.    10 — Distributing  the   second   applicatii 
from  which  the  plow  and  covering  disks  have  been  r 


of   fertilizer   with  the  potato  planter 
loved.    Aroostook  County,  Me. 


The  limiting  factor  in  the  use  of  commercial  fertilizers  in  any 
community  is  that  of  the  benefits  derived  from  their  use  rather 
than  their  cost.  As  long  as  the  increase  in  yield  due  to  the  applica- 
tion of  commercial  fertilizers  is  more  than  sufficient  to  offset  their 
cost,  the  grower  should  make  use  of  them.  It  is,  of  course, 
desirable  to  determine  by  experimentation  just  what  element  or 
elements  are  lacking  in  the  soil,  ])efore  engaging  in  any  extensive 
use  of  commercial  fertilizers. 

Method  of  Application. — Farm  manures  may  ])e  l)roadcasted 

on  the  land  by  hand  or  with  a  manure  spreader,  either  before  or 

after  the  land  is  plowed.    Some  growers  prefer  to  plow  the  manure 

under  while  others  favor  its  application  to  the  plowed  land.     When 

3 


34 


FOOD  REQUIREMENTS— HOW  SUPPLIED 


the  land  is  plowed  in  the  fall  and  it  is  not  of  a  leachy  nature,  it 
is  believed  that  better  results  will  be  secured  by  turning  the  manure 
under.  When  it  is  applied  in  the  spring  to  either  fall-  or  spring- 
plowed  land,  the  application  should  be  made  before  it  is  disked, 
in  other  words,  to  secure  the  best  results  from  the  manure  it  is 
necessary  to  have  it  tlioroughly  incorporated  with  the  soil.  Farm 
manures  should  not  be  applied  to  land  known  to  be  infested  with 
the  potato  scab  organism,  as  it  is  almost  certain  to  increase  the 
number  of  infected  tubers.  On  such  soils  it  is  preferable  to  apply 
the  manure  to  the  preceding  crop.     There  is  less  likelihood  of 


Fig.  11. — Broadcasting  the  second  application  of  fertilizer.     Aroostook  County,  Me. 

injury  to  the  tubers  when  the  manure  is  applied  to  land  in  the  late 
summer  or  early  autumn  and  then  plowed  under. 

In  the  case  of  commercial  fertilizers,  the  method  of  application 
varies  with  the  cultural  practices  followed  in  planting  the  crop. 

Where  tlie  horse-drawn  automatic  or  semi-automatic  potato 
planters  are  used,  they  are  generally  equipped  with  a  fertilizer  dis- 
tributing attachment  which  opens  up  a  shallow  furrow  and  drops 
the  fertilizer,  which,  in  turn,  is  mixed  with  the  soil  by  the  plow 
immediately  in  the  rear  of  the  fertilizer  dropi)ing  tube,  which  opens 
a  slightly  deeper  furrow  for  the  reception  of  the  seed  pieces  that  are 
dropj)ed  immediately  behind  it.  In  New  Jersey,  Long  Island,  N.Y., 
and  Maine  it  is  customary  to  apply  the  full  amount  of  fertilizer 
when  planting  the  crop.  A  few  growers,  however,  prefer  to  make  a 
second  application.  Generally  these  are  growers  who  apply  over 
a    ton    per    acre    to    the    crop.      Such    growers    usually    apply 


COMMERCIAL  FERTILIZER 


35 


about  1500  pounds  per  acre  at  the  time  of  planting,  and  make  the 
second  application  of  from  500  to  1000  pounds  over  the  row,  just 
as  the  plants  are  about  to  push  through  the  surface  of  the  ground. 
This  is  usually  done  with  the  planter  by  removing  the  plow  and 
covering  attachment  (Fig.  10).  The  fertilizer  is  either  lightly 
harrowed  in,  or  is  covered  over  with  soil.  In  some  few  instances 
a  lime  distributor  is  used  in  making  the  second  application 
(Fig.  11).  This  broadcasts  the  fertilizer  which  is  then  cultivated 
into  the  soil. 

In  the  South  where  the  horse-drawn  potato  planter  is  not  exten- 


FiG.   12. — Applying  fertilizer  with  a  3-row  Fig.  13. — Mixing  fertilizer  in  soil  with 

distributor.  one-horse  cultivator.     Deep  Creek,  Va. 

sivcly  used,  or,  if  employed,  does  not  have  a  fertilizer  distributing 
attachment,  the  common  practice  is  to  open  furrows  with  a  one 
or  two-horse  turning  plow  or  a  middle  buster,  and  then  sow  the 
fertilizer  in  the  furrow  by  means  of  a  three  or  four-row  fertilizer 
distributor,  (Fig.  12)  or  with  a  one-row  drill.  The  fertilizer 
is  mixed  with  the  soil  by  running  a  one-horse  cultivator  through 
the  furrow  (Fig.  13).  The  cultivator,  when  used  for  this  purpose, 
is  made  as  narrow  as  possible.  In  some  sections,  particularly 
ill  the  Norfolk  district,  the  growers  make  two  applications  in 
the  furrow  prior  to  planting.  Both  are  made  in  the  manner  des- 
cribed; the  first  being  applied  a  week  or  ten  days  in  advance  of 
planting,  and  the  second  just  before  the  seed  is  dropped.  The 
growers  have  a  theory  that  the  earlier  application  undergoes  cer- 
tain chemical  changes  in  the  soil,  which  render  its  plant  food  more 
readily  available  to  the  potato  plant  when  it  begins  to  push  out 
its  roots  in  quest  of  food.     It  has  seemed  to  the  writer  that  this 


3&  FOOD  REQUIREMENTS— HOW  SUPPLIED 

practice  has  at  least  one  disadvantage  in  that,  when  heavy  rains 
occur  between  the  time  of  its  application  and  the  planting  of  the 
seed,  a  large  portion  of  the  soluble  plant  food  is  washed  away. 
Later  api)lications  are  frequently  made  by  the  Southern  truck 
growers.  These  are  referred  to  as  side-dressings,  so  named  because 
the  fertilizer  is  distributed  along  the  side  of  the  row  after  the 
jilants  have  attained  some  size.  This  practice  is  often  resorted  to 
after  the  plants  have  received  a  check  due  to  cold  weather  or  a 
drought,  in  order  to  stimulate  a  quick  gro^^i;h.  The  fertilizer  is 
oftentimes  distributed  by  hand,  but  it  may  be  applied  with  a  one- 
row  drill.  When  a  side-dressing  is  a])plied,  it  is  innuediatoly 
worked  into  the  soil. 

A  successful  grower  in  New  York  State  broadcasts  the  major 
portion  of  his  fertilizer  application  before  second-plowing  his  po- 
tato land  in  the  spring.  The  reason  given  for  this  practice  is  that 
it  places  the  commercial  fertilizer  several  inches  below  the  surface 
of  the  soil  and,  at  the  same  time,  distributes  it  uniformly  over  the 
whole  area,  thus  compelling  or  stimulating  tlie  roots  of  the  plant 
to  penetrate  deeper  into  the  soil,  as  well  as  to  send  out  their  laterals 
in  all  directions  in  quest  of  the  plant  food  contained  in  the  fer- 
tilizer. Through  the  development  of  this  extensive  root  system, 
the  plant  is  better  able  to  withstand  drought  or  other  unfavorable 
conditions  and  in  consequence  thereof  can  be  counted  on  to  give  a 
better  yield,  one  year  Avith  another,  than  will  those  having  all  their 
plant  food  inrmediately  beneath  or  above  them,  as  is  the  case  when 
the  whole  application  is  made  in  the  drill  row.  In  the  particular 
example  just  cited,  the  crop  grown  is  a  late  one.  It  is  doubtful 
if  such  a  practice  would  be  desirable  in  the  growing  of  an  early 
crop,  as  earliness  of  maturity  is  the  prime  consideration. 

QUESTIONS    ON   THE   TEXT 

1.  Wliat  is  the  jyrower's  problem  as  regards  an  ample  food  su])])Iy? 

2.  How  many  of  the  eighty  or  more  chemical  elements   now   known  are 

found  in  plants?     Name  them. 
.'!.  Which  of  the  elements  are  generally  considered  Ihe  essential  ones? 

4.  Which  are  most  commonly  deficient  in  your   local   soils? 

5.  What  element  or  elements  are  lacking  in   tlie   Inter-iMountain   section 

of  the  United  States? 
f).  Tn  general  what  do  the  soils  of  the  northeastern  United  States  require? 

7.  What  are  the  relative  amounts  of  nitrogen,  phosphoric  acid  and  potash 

removed  hy  a  200-bushcl-per-acre  crop  of  potatoes? 

8.  How  much  nitrate  of  soda,   l(i  per  cent  acid  phosphate,  and  muriate 

of  potash  would  be  required  to  supply  this  loss  to  the  soil? 

9.  What  sources  of  plant  food  may  lie  use  in  the  enrichment  of  his  soil? 


QUESTIONS  SUGGESTED  BY  THE  TEXT  37 

10.  Explain   the  term   "{ireen  iiiamuiiii;"  aTid   yive  a   c-oncrete   example   of 

its  use. 

11.  What  leguminous  and  nun-le-iuminous  crops  are   most  generally   used 

for  the  enrichment  of  the  soil? 

12.  What  stage  of  maturity  should  a  crop  reach  before  turning  it  under 

in  order  to  secure  a  maxinuun  amount  of  benefit? 
l.'l.  How   does    the   nitrogen,    phosphoric    acid,    and    potash    content    of   an 
alfalfa    crop    compare    witli   tliat    of    the    other    leguminous    crops 
mentioned  in  the  legume  table? 

14.  What  is  the  average  percentage  content  of  nitrogen,  phosphoric  acid, 

and  potash  of  a  reasonably  good  grade  of  farm  manure? 

].").  How  many  pounds  of  each  would  be  added  by  an  application  of  ten 
tons  of  manure  per  acre? 

10.  What  proportion  of  the  plant  food  elements  in  farm  manures  are 
availalile  to  the  crop  to  which  it  is  applied? 

17.  What  supplementary  fertilizing  material  is  it  advisable  to  use  in  con- 
nection with  farm  manures  in  sections  where  the  mineral  elements 
are  lacking? 

15.  Where  entire  dependence  is  to  l)e  placed   on   farm  manures,  when  are 

they  best  applied?     Give  reason. 
1!).  \\'hy  does  the   southern   potato  grower  use  a  different  grade  of  com- 
mercial fertilizer  from  that  of  the  northern  grower? 

20.  What    fertilizer    formula    is    used   rather    extensively   in    the    Norfolk 

trucking  section? 

21.  What  is  a  favorite  formula  in  Aroostook  County,  Maine? 

22.  What  was  the  result  of  using  a  no-potash  fertilizer? 

28.  What  amount  of  commercial  fertilizer  is  it  advantageous  to  use? 

24.  ^\'hat  is  the  probability  of  potato  growers  in  the  Middle  West  l)ecom- 

ing  large  users  of  commercial  fertilizers? 

25.  What  is  the  best  way  of   determining   what  plant   food   elements   are 

lacking  in  any  particular  soil? 
20.  Are  there  any  disadvantages  in  the  use  of  farmyard  manures?     Give 
reasons. 

27.  How  may  the  possibility  of  injury  from  common  scab  be  avoided? 

28.  How   are   commercial   fertilizers   usually   applied   to   the   land    in   the 

North?     In  the  South? 
20.  \Vhat  is  the  theory  involved  in  applying  a  part  of  the  fertilizer  some 

days  in  advance  of  planting  the  crop? 
30.  What  is  meant  by  a  side-dressing?     How  is  it  applied? 

QUESTIONS  SUGGESTED  BY  THE  TEXT 

1.  What  amounts  of  farm  manure  are  applied   to  potato  fields  by  local 

growers  ? 

2.  What    legume    crops    are    commonly    turned    under     for     local     crops 

of  potatoes? 

3.  Calculate    the    amoTUits    of    the    three    fertilizing    constituents    applied 

in  these  ways  by   one  grower. 

4.  What  fertilizer  formulas  are  used  by  local  growers? 

References   Cited 

1.  Van  Slyke,  L.  L.     Fertilizer  and  Crops,     pp.   15,  163,  289,  556,  1917. 

2.  Alabama   Sta.   Bid.    14    (n.    ser.)       1890,   pp.    5-9. 

3.  New  Jersey  Sta.  Rpt.   1893,  pp.   140-150. 

4.  South  Carolina  Sta.  2nd.  Ann.  Rpt.  pp.  169-179. 


CHAPTER  VI 
'  CROP  ROTATION 

Necessity  of  Crop  Rotation. — A  system  of  agriculture  which 
is  not  based  on  a  definite  rotation  of  crops  can  hardly  be  regarded 
as  measuring  up  to  modern  agricultural  teachings.  The  theory 
on  which  crop  rotation  is  based  is  that  of  conserving  the  natural 
fertility  of  the  soil  by  maintaining  a  proper  balance  between  its 
mineral  elements,  sustaining  or  increasing  the  humus  content, 
thereby  improving  its  physical  condition  and,  at  the  same  time, 
restraining  the  development  of  injurious  fungous  and  insect  pests. 
Bolley^  has  recently  demonstrated  that  the  constantly  diminishing 
wheat  yield  in  the  Middle  West  is  not  so  much  due  to  a  depletion 
of  soil  fertility  as  to  the  cumulative  effect  of  constantly  increasing 
soil  infection  by  fungi  preying  upon  the  roots  of  the  growing  wheat 
plants.  He  has  also  found  that  a  rotation  of  crops  on  these  lands 
has  served  to  give  increased  wheat  yields,  when  this  cereal  followed 
other  crops  such  as  corn,  oats  or  potatoes,  in  the  rotation  scheme. 

Systems  of  Crop  Rotations. — At  the  present  time,  compara- 
tively few  American  potato  growers  practise  a  definite  crop  rota- 
tion system,  whereby  but  one  crop  of  potatoes  is  grown  during  the 
rotation.  For  example,  in  the  far-famed  Aroostook  County  in 
northern  Maine,  where  the  potato  may  be  said  to  be  the  only  cash 
crop  grown  by  a  majority  of  the  farmers,  it  is  generally  understood 
that  a  three  year  rotation  is  practised.  Theoretically^,  the  rotation 
is:  potatoes  the  first  year,  oats  seeded  with  clover  and  timothy  the 
second,  and  a  clover  crop  the  third  year.  The  clover  rowen,  or 
second  crop  clover,  is  plowed  under  in  the  late  summer  or  early 
autumn  for  the  ensuing  potato  crop.  As  a  matter  of  fact,  however, 
comparatively  few  Aroostook  farmers  adhere  to  this  rotation.  A 
large  proportion  of  them  take  two,  three,  or  even  more  potato  crops 
in  succession  before  the  land  is  seeded  do^vn.  This  is  particu- 
larly true  on  land  which  is  especially  well  adapted  to  potatoes. 
Fields  have  ])een  noted  during  the  past  two  seasons  that  were  pro- 
ducing their  ninth  consecutive  crop  of  potatoes.  Such  extreme 
cases  of  cropping  are,  of  course,  comparatively  rare ;  but  the  taking 
of  two  or  three  crops  in  succession  is  quite  common.  On  the  other 
hand,  however,  here  and  there  may  be  noted  a  grower  who  is 
adhering  to  a  well-defined  system  of  crop  rotation.    The  author 


INTERPLANTING 


39 


has  in  mind  one  party  wlio  for  years  has  been  practising  a  five  year 
rotation  system,  allowing  the  land  to  remain  in  grass  three  years, 
instead  of  one.  On  this  farm  fifty  acres  of  potatoes  are  grown 
annually.  It  is  hardly  necessary  to  say  that,  under  this  system  of 
cropping,  profitable  yields  of  high  class  potatoes  are  being  secured. 
Interplanting. — In  the  trucking  regions  of  the  Atlantic  sea- 


m&\ 


Fig.  14. — Potatoes  interplanted  with  corn. 


board,  from  New  Jersey  to  Florida,  a  peculiar  system  of  cropping 
is  in  vogue. 

In  Florida,  for  example,  the  potato  crop  is  planted  from  the 
latter  part  of  December  to  the  middle  of  February,  and  is  harvested 
from  the  latter  part  of  March  to  the  latter  part  of  Ma.j.  The  land 
is  very  frequently  planted  to  corn,  and  occasionally  to  sugar  cane, 
some  time  in  advance  of  harvesting  the  potato  crop.  In  the  case 
of  the  corn,  the  planting  is  usually  done  with  a  one-horse  planter, 
so  constructed  that  the  seed  dropping  attachment  is  set  to  one  side 
of  the  center,  which  permits  the  drilling  in  of  the  corn  on  the  side 
of  the  potato  ridge  (Fig.  14).  When  the  harvesting  of  the  potatoes 
is  delayed  by  unseasonable  weather,  or  by  unfavorable  prices,  the 
corn  plants  frequently  attain  a  height  of  six  to  twelve  or  more 
inches  before  the  potatoes  are  removed  (Fig.  15). 


40  CROP  ROTATION 

In  sucli  instances,  of  course,  and  in  fact  iti  all  cases  where  the 
sides  of  the  potato  ridges  are  planted  Avith  corn,  the  harvesting  of 
the  crop  is  very  largely  done  by  hand.  By  exercising  a  reasonable 
degree  of  care  it  is  possible,  by  using  a  small  one-horse  turning 
plow,  to  plow  out  the  potatoes.  This  materially  reduces  the  hand 
work  and  effects  a  considerable  saving  in  labor  cost. 

The  sugar  cane  cuttings  are  usually  embedded  near  the  bottom 
of  the  furrow,  and  are  suiiiciently  removed  from  the  potato  plants 
to  alloAV  the  use  of  a  potato  digger. 

Annual  Crop  After  Potatoes. — AVhere  interplantiiig  is  not 
practised,  the  land  may  be  plaiited  to  corn  as  soon  as  the  potatoes 


Fia    1")  — \  iiowlv  }iarvested  potato  Ti  1  uit,-;.     Ordinarily  it  is 

iiut  considered  desirable  lo  have  the  intercrop  rr^i  lar  au\aniia  luiHiiliie  i)otato  crop  is  re- 
moved.    Hastings,  Fla. 

are  out  of  the  ground ;  or  the  seed  is  dropped  in  the  furrow  between 
the  rows  prior  to  digging.  The  operation  of  harvesting  the  crop 
covers  the  corn.  Or  it  may  be  seeded  to  crab-grass  and  allowed  to 
produce  a  crop  of  hay.  When  planted  to  corn,  cowpeas  are  very 
frequently  sowed  among  the  corn  at  the  time  it  receives  its  final 
cultivation.  The  cowpeas  make  a  fair  growth  of  vine,  conserve 
and  accumulate  nitrogen  in  the  soil,  and  at  the  same  time  provide 
a  considerable  quantity  of  vegetable  matter  to  be  plowed  under 
for  the  next  season's  crop  of  potatoes,  or  it  may  be  made  into  hay. 
On  most  of  the  potato  farms  around  Hastings,  Fla.,  a  crop  of  early 
potatoes  is  produced  every  season,  with  seemingly  little,  if  an)^, 
deleterious  results,  where  intelligent  care  is  given  to  the  preparation 
of  the  land  and  the  care  of  the  crop. 


POTATOES  CONTINUOUSLY 


41 


What  has  been  said  regarding  Florida  conditions  applies  almost 
equally  well  to  the  Charleston,  S.  C,  district.  That  is,  the  potato 
cro])  is  followed  by  corn,  cowpcas,  cotton,  or  hay. 

Strawberries  with  Potatoes. — In  the  Norfolk  and  Eastern 
Shore  trucking  regions  of  Virginia  and  Maryland,  various  rota- 
lion  and  intercropping  methods  are  pursued.  One  rotation,  fre- 
quently observed  by  the  writer,  is  that  of  interplanting  the  potato 
field  with  strawberry  plants.  When  this  practice  is  followed,  the 
potato  rows  are  spaced  from  foUr  to  five  feet  apart,  the  young 
strawberry  plants  being  set  between  the  rows   (Fig.  16).     In  this 


Fig.  16. — Strawberry  rows  five  feet  apart  interplanted  with  potatoes.     Norfolk,  Va. 

way  a  partial  crop  of  potatoes  is  secured  while  the  berry  plants 
are  becoming  established.  Another  way  is  to  interplant  with  string 
beans,  or  with  corn,  when  an  early  crop  is  desired.  Where  the 
potato  crop  is  the  sole  occupant  of  the  land  during  its  growing 
period,  it  may  be  followed  with  a  crop  of  co^vpeas,  soybeans,  millet, 
or  corn.  Occasionally  a  second  crop  of  potatoes  may  be  grown. 
It  is  not  an  infrequent  practice  to  grow  potatoes  two  or  three 
years  in  succession  on  the  same  land.  There  is  no  distinctive  crop 
rotation  system  between  which  might  be  said  to  apply  to  this 
trucking  section. 

Potatoes  Continuously. — In  addressing  an  audience  of  potato 
growers  in  the  Louisville,  Kentucky,  district  some  time  ago,  the 


42  CROP  ROTATION 

author  \yas  greatly  surprised  to  have  a  gentleman  arise  at  the  close 
of  the  meeting  and  make  the  statement  that  he  had  heen  annually 
removing  two  crops  of  potatoes  from  land  that  has  heen  devoted 
to  this  system  of  cropping,  to  his  actual  knowledge,  for  33  years. 
He,  furthermore,  stated  that  he  had  been  unahle  to  detect  any 
diminution  in  the  crop,  and  was  even  inclined  to  believe  that 
better  yields  were  being  secured  now  than  formerly.  Fortunately, 
such  severe  cropping  is  extremely  rare.  It  is  a  common  practice 
in  that  section,  however,  to  repeatedly  grow  one  crop  of  potatoes 
per  year  on  the  same  piece  of  ground.  Such  a  practice  can  hardly 
be  regarded  as  a  wise  policy  to  pursue  on  any  soil  or  in  any  locality. 

Potatoes  After  Alfalfa. — In  the  "Western  potato  producing 
centres,  such  as  the  Greeley  and  Carbondale  districts  in  Colorado, 
a  fairly  definite  crop  rotation  system  is  followed.  For  example, 
in  the  Greeley  section  potatoes  are  usually  planted  on  an  alfalfa 
sod  land.  When  potato  production  was  at  its  zenith  in  this  locality, 
potatoes  frequently  followed  potatoes  for  two  or  three  years  in 
succession.  At  present  sugar  beets  may  alternate  Avith  potatoes, 
after  which  one  or  two  grain  crops  follow  before  seeding  it  back 
to  alfalfa,  in  Avhich  crop  it  may  remain  from  three  to  four  years. 
Some  growers  secure  two  crops  of  potatoes  in  the  rotation  scheme; 
the  first  being  grown  on  alfalfa  sod,  after  which  a  crop  of  grain 
follows  and  then  a  second  crop  of  potatoes.  When  potatoes  follow 
potatoes,  the  second  crop  from  alfalfa  sod  is  frequently  better  than 
the  first  one.  These  results  are  obtained  only  when  the  land  is 
reasonably  free  from  infectious  diseases  that  prey  upon  the  po- 
tato plant. 

At  the  Greeley  Experiment  Station,  operated  conjointly  by  the 
United  States  Department  of  Agriculture,  the  Weld  County  Com- 
missioners and  the  Colorado  State  Experiment  Station,  a  definite 
four  year  crop  rotation  has  been  established,  in  which  potatoes  are 
grown  on  alfalfa  sod,  followed  the  next  season  by  oats  seeded  with 
alfalfa,  the  oats  serving  as  a  nurse  crop,  and  indirectly  returning 
a  fair  yield  of  grain;  alfalfa  is  grown  the  following  two  seasons. 
The  same  rotation  has  been  established  at  the  Jerome  Experiment 
Station,  Jerome,  Idaho,  which  is  being  operated  by  the  United 
States  Department  of  Agriculture. 

In  the  Carbondale  district  a  very  similar  system  of  crop  rota- 
tion is  in  vogue,  except  that  sugar  beets  are  not  grown  in  that 


ALFALFA  IN  THE  ROTATION  43 

region.     The  general  practice  is  to   take   two   crops   of  potatoes 
in  succession. 

Potato-Barley  Rotation. — In  the  "tule"  lands  of  the  Sacra- 
mento and  San  Joaquiii  delta,  regions  where  potatoes  have  been 
tlie  chief  money  crop  for  a  number  of  years,  the  common  practice 
is  to  take  two  or  three  potato  crops  in  succession,  followed  by  a 
crop  of  barley,  and  then  back  to  potatoes  for  another  two  years. 
The  result  of  such  a  system  of  crop  rotation  has  been  to  so  thor- 
oughly infect  the  soil  with  potato  diseases  as  to  make  the  crop,  in 
many  instances,  an  unprofitable  one  to  grow. 

No  Uniform  Rotation. — From  the  foregoing  statements,  it 
is  evident  that  there  is  no  general  and  well-defined  system  of  crop 
rotation  that  is  rigidly  adliered  to  in  any  of  the  large  potato  grow- 
ing centres.  The  desirability  of  rotating  crops  is  well  understood, 
but  the  temptation  to  grow  a  money  crop  as  often  as  possible  is 
great;  so  that  the  ultimate  benefits  accruing  from  the  practice  of 
a  sane  crop  rotation  system,  are  often  sacrificed  to  the  prospect 
of  immediate  gain. 

A  potato  crop  rotation  system  suitable  to  each  potato  producing 
section  could  easily  be  adopted  if  the  growers  desired. 

The  three-year  system,  supposedly  practised  by  the  Maine 
potato  growers,  is  probaljly  as  desirable  as  could  be  devised  for 
that  section.  As  a  rule,  a  good  clover  stand  is  easily  secured;  and 
the  crop  grows  luxuriantly,  so  it  affords  a  cheap  source  of  plant 
food  and  serves  to  maintain  and  even  increase  the  humus  content  of 
the  soil,  thereby  keeping  it  in  good  physical  condition. 

Alfalfa  in  the  Rotation. — Where  alfalfa  can  be  grown  as  suc- 
cessfully or  more  so  than  clover,  it  should  be  substituted  for  it, 
a. id  at  least  a  four  year  rotation  adopted.  It  may  be  that,  where 
it  seems  desirable  to  allow  the  land  to  remain  in  alfalfa  three  or 
four  years,  two  crops  of  potatoes  may  be  permissible  in  the  rotation 
by  growing  a  crop  of  grain  between  them. 

The  following  rotations  are  suggested  for  alfalfa  growing 
sections : 

I.  1st  year,  potatoes  on  alfalfa  sod;  2nd  year,  oats,  wheat  or 
barley  seeded  with  alfalfa;  3rd  and  4th  years,  alfalfa. 

II.  1st  year,  potatoes  on  alfalfa  sod;  2nd  year,  wheat;  3rd 
year,  potatoes;  4th  year,  oats  or  barley  seeded  with  alfalfa;  5th, 
6th  and  7th  years,  alfalfa. 


44  CROP  ROTATION 

For  clover  growing  sections  wli('r(>  aH'alfa  doot^  not  succccmI, 
two  rotations  are  hero  given  : 

I.  1st  year,  potatoes  on  clover  sod;  2nd  year,  oats  or  barley, 
seeded  down  with  clover,  timothy  and  red  top ;  3rd  year,  hay. 

IT.  1st  year,  potatoes  on  clover  sod;  2nd  year,  oats  or  barley, 
seeded  v\"ith  clover,  timothy,  bluegrass  and  redtop;  3rd  and  4th 
years,  hay. 

In  the  trucking  sections  oC  the  South  the  diversity  of  crops 
grown,  and  the  fact  that  two  or  three  truck  crops  may  be  grown 
annually,  makes  the  task  of  devising  a  suitable  crop  rotation  system 
an  extremely  perplexing  one.  Where  careful  attention  is  given 
to  the  plowing  under  of  cover  crops,  potatoes  may  follow  potatoes 
3'ear  after  year,  with  apparently  little,  if  any,  diminution  in  yield 
or  in  quality.  On  the  other  hand,  a  safer  and  saner  plan  to  follow 
would  be  not  to  grow  potatoes  oftener  than  once  in  two  years; 
always  planning  to  turn  under  some  cover  crop  for  the  ensuing 
crop  of  potatoes. 

QUESTIONS    ON    THE   TEXT 

1.  On  what  is  the  theory  of  crop  rotation  baaed? 

2.  What  has  Bolley  demonstrated  to  be  one  of  the  reasons  at  least,  for 

the  constantly  diminishing  wheat  yield  in  the  Middle  West? 
'!.  What    crop    rotation    is    supposed    to   be    followed    by   the    Aroostook, 
Maine,  potato  grower? 

4.  What  is  the  actual  practice  of  a  large  majority  of  the  Maine  growers? 

5.  What  system  of  crop  rotation  is  followed  in  Florida? 

6.  What  is  the  system  of  crop  rotation  practised  in  the  trucking  regions 

of  Virginia  and  Maryland? 

7.  What  rotation  is  practised  in  the  Louisville,  Kentucky,  district? 

8.  What  is  the  practice  in  Colorado  and  other  western  states? 

9.  What  is  the  crop  rotation  system  followed  at  the  Greeley  and  Carbon- 

dale  Stations? 

10.  Give  crop  rotation   system   followed   in   the   reclaimed   "tule"   lands   of 

the  Sacramento  and  San  Joaquin  delta  regions  of  California. 

11.  What  crop  rotation  system  is  thought  most  desirable  for  the  Maine 

potato  grower? 

12.  What  are  the  relative  values  of  clover  and  alfalfa? 
i;{.  Give  four-year  rotation  suggested  with  alfalfa. 

14.  Give  seven-year  rotation  suggested  with  alfalfa. 
If).  Give  three-year  rotation  suggested  with  clover. 

16.  Give  four-year  rotation  suggested  with  clover. 

17.  What  problems  confront  one  in  devising  an   acceptable  crop   rotation 

system  for  the  southern  grower? 


QUESTIONS  SUGGESTED  BY  THE  TEXT  45 

QUESTIONS   SUGGESTED  BY  THE  TEXT 

1.  Give  the  most  common  rotation  Ity  local  potato  {^rowers. 

2.  What  is  the  next  most  common?     Give  any  other  rotation  in  use. 

3.  Compare  and  criticise  these  rotations. 

4.  Describe  any  interplanting  with  potatoes  which  you  have  seen. 

5.  What  bad  effects  have  local  growers  had  from  too  continuous  cropping 

of  the  same  soil  with  jJotatoesV 

References   Cited 

BoLLEY,  H.  L.  1909.  Deterioration  in  wheat  yields  due  to  root-rots  and 
blight-producing  diseases.  N.  D.  ma.  Press  Bui.  33:  1-4,  Oct.,  1909- 
re-edited  Dec.   1911. 


CHAPTER  VII 

VARIETIES  TO  GROW,  KIND  AND  AMOUNT  OF 
SEED  TO  USE,  AND  PLANTING  METHODS 

Choice  of  Varieties. — The  first  question  to  decide  in  the  pro- 
duction of  a  crop  of  potatoes  is  that  of  the  variety  to  grow.  A 
variety  should  be  selected  that  is  adapted  to  the  region  in  which 
it  is  to  be  grown.  As  a  rule  varietal  adaptations  are  now  fairly 
well  recognized  in  most  large  potato  producing  centers  or  districts. 
If  the  crop  to  be  produced  is  intended  to  supply  an  early  market 
it  will,  of  course,  necessitate  the  choice  of  an  early  variety.  The 
choice  of  a  variety  must,  therefore,  be  governed  by  its  adaptability 
to  its  environment,  and  the  season  of  the  year  in  which  it  is  to  be 
marketed.  There  is  one  other  consideration  in  the  choice  of  a 
variety,  and  that  is  whether  it  is  to  be  growai  for  seed  or  for  table 
purposes  and  whether  the  tuber  is  rough  or  smooth  (Fig.  17). 
The  leading  commercial  varieties  of  potatoes  are  rather  few  in 
number  compared  with  the  long  list  of  varieties  or  varietal  names 
catalogued  by  the  seedsmen  of  this  country.  The  following  list 
is  believed  to  include  all  the  varieties  of  strictly  commer- 
cial importance. 

Early  Varieties  Medium  or  late  maturing  varieties 

Irish   Cobbler  Burbank  Pearl 

Triumph  Russet  Burbank       McCormick 

Early  Ohio  Rural  Perfect  Peachblow   (Red  McClure) 

Spaulding   No.   4      Russet  Rural  Brown  Beauty 

Green   Mountain       American  Giant 

Chas.  Downing   (Idaho  Rural) 

To  this  number  might  be  added  a  supplementary  list  of 
varieties,  such  as  the  Early  Rose,  Beauty  of  Hebron,  White  Rose, 
and  Up-to-date. 

As  the  above  varieties,  vni\\  but  two  or  three  exceptions,  are 
discussed  in  more  or  less  detail  in  Chapter  XXII,  further  elabora- 
tion is  unnecessary,  beyond  saying  that  it  should  be  understood 
that  the  Green  Mountain,  Rural,  Burbank,  etc.,  include  the  various 
members  of  the  groups  tliey  represent.  The  Brown  Beauty  is 
evidently  a  variety  of  English  origin  as  yet  unidentified.  It  is  the 
leading  variety  grown  in  the  San  Luis  Valley  district  in  Colorado 
46 


GOOD  SEED  DEFINED 


47 


where  it  is  very  popular.  The  White  Eose  is  a  popiiLar  variety 
in  certain  sections  of  California.  A  variety  masquerading  under 
the  name  of  the  Oregon  White  Rose,  and  another  under  the  name 
of  British  Queen  have  become  popular  in  western  Oregon  and  cer- 
tain localities  in  California.  The  two  varieties  seem  to  be  identical 
and  both  are  improperly  named.  Our  own  observations  lead  us  to 
believe  that  they  belong  to  the  Up-to-Date  group  of  ])otatoes. 


Fig.  17.— ^A  uniform  lot  of  high  grade  seed  stock,  grown  on  the  Sweet  ranch,  Carbon- 
dale,  Col. 

Kind  of  Seed  to  Use. — The  importance  of  using  good  seed 
potatoes  can  scarcely  be  overemphasized.  The  customary  practice 
of  using  what  is  left  from  the  season's  crop,  after  marketing  or 
consuming  the  best  of  it,  must  be  discontinued  if  the  present  quality 
and  yield  of  the  potato  is  to  be  materially  improved  or  increased. 
It  is  as  useless  for  the  potato  grower  to  expect  maximum  yields 
from  inferior  seed  stock,  as  for  the  dairyman  to  hope  to  develop 
a  superior  milking  strain  from  scrub  stock.  Nature  does  not  work 
in  tliat  way. 

Good  Seed  Defined. — Good  seed  mav  be  described  as  stock 


48 


PLANTING  METHODS 


GOOD  SEED  DEFINED 


49 


tliat  is  pure  Avitli  rospect  to  the  yariety;  that  has  heen  produced 
by  healthy,  vigorous,  heavy-yielding  plants  grown  under  favorable 
climatic  conditions;  that  is  somewhat  immature,  reasonably  uni- 
form in  size  and  sha|iO  (Figs.  18  to  21),  and  firm  and  sound,  with 
the  first  sprouts  beginning  to  develop  at  planting  time.  vSeed  of 
this  character  is  now  procurable  in  somewhat  limited  quantities 
from  growers  who  have  recently  begun  to  specialize  in  seed  produc- 
tion in  Maine,  Vermont,  New  York,  New  Jersey,  Maryland,  West 


Fig.  19. — Seed  tubers  showing  desirable  stage  of  germination;  first  sprouts  just  pushing  out. 

Virginia,  Michigan,  Wisconsin,  Minjiesota,  Nebraska,  Colorado, 
Idaho,  Oregon,  Washington,  and  California.  In  all  of  these  states 
provision  has  been  made  for  the  inspection  and  certification  oi' 
the  seed  stock  of  growers  who  have  made  proper  application  for 
such  inspection  service,  and  whose  fields  and  the  crop  harvested 
from  same  have  been  found  to  fulfil  the  inspection  requirements. 
As  yet,  the  amount  of  seed  available  in  these  various  states  rep- 
resents but  a  small  fraction  of  that  required  for  planting  the  total 
acreage  of  the  state  or  the  country  as  a  whole. 

Certified  seed  necessarily  commands  a  considerable  premium 
over  that  which  has  not  been  inspected,  but  the  extra  cost  of  the 


50 


PLANTING  METHODS 


&5 


i'ry«'-"i>K«isr 


.,.     S 


GREENING  AND  GERMINATING 


51 


seed  is  slight  as  compared  to  the  increased  yields  which  may  be 
expected  from  tlie  use  of  good  seed  and  the  crop  insurance  which 
it  affords. 

Seed  disinfection  is  discussed  in  the  chapter  on  diseases. 

Greening  and  Germinating  or  Sprouting  Seed. — The  practice 
of  greening  and  germinating  seed  potatoes  before  planting  them, 
in  order  to  hasten  the  development  of  marketable  tubers,  is  one 
that  is  (^ommonly  employed  by  growers  of  early  potatoes  in  Great 
Britain  and  on  the  Continent,  but  is  little  used  by  American 
growers.     The  British  growers  use  a  special  seed  tray  or  flat,  con- 


FiG.  21. — Greened  and  well-germinated  Irish  Cobbler  seed  tuber.  These  sprouts  are 
about  the  right  stage  of  development.  Note  how  short  and  stubby  they  are.  Such  sprouts 
are  tough  and  are  not  easily  broken  off. 

structed  with  corner  posts  from  four  to  five  inches  higher  than  the 
sides,  to  which  a  narrow  strip  of  board  is  nailed  across  the  upper 
end.  This  strip  serves  as  a  handle  in  lifting  or  moving  the  flats 
and,  when  tiered  one  above  another  in  the  germinating  room  or 
house,  provides  an  open  space  between  the  flats.  The  dimension 
of  the  tray  is  immaterial,  except  that  it  should  be  of  a  convenient 
size  to  handle.  A  tray  having  an  outside  dimension  of  16  by  30 
by  3  inches  has  been  found  by  the  writer  to  be  very  convenient  to 
handle  (Fig.  22).  Such  a  tray,  when  filled  with  medium  sized 
tubers,  will  hold  approximately  fifty  pounds.  The  primary  object 
of  the  flats  is  to  furnish  a  convenient  receptacle  for  the  selected 
seed  tubers,  in  which  to  expose  them  to  light  and  sufficient  heat 


52 


PLANTING  METHODS 


to  induce  slow  growing  hut  vigorous  terminal  sprouts.  The  tubers 
are  placed  in  the  flats  with  the  seed  end  up})erniost,  with  usually 
l)ut  one  layer  to  a  Hat.  By  placing  the  seed  end  uppermost  it 
tends  to  stimulate  the  development  of  strong  sprouts  from  the  bud 
eye  clusters,  which,  in  the  presence  of  light,  remain  short  and  stubby 
and  are  not  easily  broken  oflP  (Fig.  21).  Many  of  the  English 
growers  place  their  seed  in  the  trays  in  the  autumn  or  early  winter. 
Under  favorable  conditions,  a  development  similar  to  that  shown 
in  figure  23  will  be  obtained  in  from  four  to  eight  weeks,  depend- 
ing on  the  season  of  the  year  in  which  they  are  placed  in  the  trays. 


Fig.  22. — Tiers  of  16x30x3  inch  slat-bottomed  seed  trays,  used  for  storing  small  lota  of 
seedling  potatoes.     Such  trays  are  suitable  for  germinating  seed  in  the  light. 

Not  all  varieties  respond  alike  to  this  treatment :  in  the  Eural,  for 
instance,  the  only  eyes  producing  sprouts  are  usually  those  of  the 
seed  end  (Fig.  21)  whereas  in  the  case  of  the  Green  Mountain, 
lateral  eyes  are  just  as  likely  to  start  into  growth  as  the 
terminal  ones. 

Where  shallow  trays  are  not  available  it  is  ])ossible  to  green  and 
germinate  tlie  seed  tubers  by  spreading  them  out  rather  thinly 
on  a  floor  or  the  ground,  Mdiere  they  can  be  protected  from  frost 
and  at  the  same  time  be  exposed  to  light  during  the  daytime. 
By  turning  over  the  tubers  every  four  or  five  days  with  a  wooden 
rake  or  a  potato  scoop  shovel,  most  of  the  tubers  will  be  exposed 
to  the  light  during  some  portion  of  the  germinating  period.     Two 


GREENING  AND  GERMINATING 


53 


to  four  weeks  exposure  will  usually  be  enough  to  start  germina- 
tion sufficiently  to  enable  the  one  who  cuts  the  seed  to  select  those 
eves  that  show  an  active  growth. 

The  benefits  derived  from  greening  and  germinating  the  seed 
before  planting  it  are  not  confined  to  the  securing  of  a  better  stand 
and  a  quicker  maturity,  but  it  is  claimed  that  a  heavier  yield  is 
also  obtained.     Greig"  reports   increased  yields  from  germiiuited 


Fig.  23. — True  to  type  Peachblow  seed  potatoes,  showing  the  master  sprout,  which  is 
the  strongest  sprout  the  potato  can  produce,  and  if  it  is  allowed  to  grow  no  other  sprout  will 
be  started.    Courtesy  L.  D.  Sweet,    Col. 

over  ungerminated  seed  of  from  34  to  39.5  bushels  per  acre.  Still 
larger  increases  are  mentioned^  in  which  gains  of  from  61.6  to 
74.7  bushels  were  obtained.  Tlie  extent  to  which  the  sprouting 
of  seed  potatoes  is  practised  in  Great  Britain  can  be  judged  from 
the  following  item  which  appeared  in  the  Agricultural  Gazette, 
volume  87,  p.  188,  1918,  "The  Food  Controller  has  decided,  in 
special  circumstances,  to  grant  licenses  to  dealers  to  sell  sprouted 
seed  potatoes  at  a  price  not  exceeding  30  shillings  per  ton  in  excess 
of  the  price  allowed  for  the  same  variety  of  unsprouted  seed  pota- 


54 


PLANTING  METHODS 


toes."     Some  of  the  larger  Jersey  Island  potato  growers  sprout 
hundreds  of  tons  of  seed  potatoes  each  year. 

In  America,  this  metliod  of  securing  earliness  of  maturity  of 
tlie  resultant  crop  offers  greater  possibilities,  in  tlie  writer's  judg- 
ment, to  tlie  growers  of  tlie  North  tlian  of  the  South.  The  reason 
for  this  is  that  the  southern  grower  ordinarily  plants  his  early 
potato  crop  when  the  groujid  is  cold,  and  while  cool  and  even  quite 
frosty  nights  prevail.     Under  these  conditions  the  seed  pieces  are 


Fig.  24. — An  extensive  root  is  developed  before  the  stems  appears  above  ground. 

slow  in  germinating,  and  it  matters  little  whether  they  are  sprouted 
before  planting  or  not,  because  the  unsprouted  seed  has  ample  time 
to  germinate  and  become  well  rooted  before  the  upper  layers  of  soil 
are  sufficiently  warm  to  stimulate  stem  growth  (Fig.  24).  It  is, 
of  course,  desirable  to  have  the  seed  exposed  to  light  and  heat  a 
week  or  two  before  planting;  but  it  is  questionable  whether  much 
benefit  is  derived  from  a  prolonged  greening,  such  as  is  practised 
by  overseas  growers. 

Size  of  Seed  Piece. — The  question  of  size  of  seed  piece  and 
whole  vs.  cut  seed  is  one  that  has  engaged  the  attention  of  growers 
and  scientists  for  over  a  century  and  is  still  not  fully  answered. 
The  superiority  of  whole  over  cut  seed  or  of  cut  seed  over  Avhole 
seed  has  been  repeatedly  demonstrated  for  both;  and  a  student 


RELATION  OF  SIZE  TO  AMOUNT  OF  SEED  PER  ACRE       55 

of  the  literature  of  tliis  subject  soon  arrives  at  a  point  where  he 
is  convinced  that  tlie  question  of  superiority  of  whole  or  of  cut 
seed  is  one  of  environment  rather  than  of  actual  influence  of  seed 
piece.  In  general,  the  experimental  evidence  indicates  rather 
clearly  that,  within  reasonable  limits,  the  larger  the  size  of  the  seed 
piece  used  the  larger  will  be  tlie  total  yield.  These  results  are  gen- 
erally secured,  however,  at  the  expense  of  size;  that  is  a  larger 
percentage  of  the  crop  will  l)e  too  small  for  tal)le  purposes.  This 
is  particularly  true  with  respect  to  wliole  seed. 

Relation  of  Size  to  Amount  of  Seed  per  Acre. — Ilardenburg^ 
as  a  result  of  a  review  of  the  literature  on  size  of  seed  piece, 
concludes  that  in  many  of  the  experiments,  false  conclusions  have 
been  reached,  through  the  neglect  of  the  investigator  to  take  into 
account  the  amount  of  seed  used  per  acre.  He  illustrates  his  point 
as  follows :  "In  tests  comparing  the  influence  on  yield  of  whole, 
half,  quarter,  and  eighth  tuljers,  the  results  have  generally  favored 
the  whole  tuber  for  seed,  and  it  has  been  concluded  that  the  larger 
the  seed  piece  planted,  the  greater  the  yield  is  likely  to  be.  In 
reality,  eight  times  as  much  seed  has  been  used  per  acre  when 
whole   seed   has   been   used   as   when    eighth   tubers    are    planted 

Most  of  these  experiments  have,  therefore  in   reality   not 

shown  that  whole  tubers  are  to  be  preferred  to  eighth  tubers, 
])rovided  the  eiglith  tubers  are  planted  enough  closer  in  the  row 
to  consume  the  same  amount  of  seed  per  acre  as  Avould  be  used 
in  case  whole  tubers  were  planted." 

In  the  main  Hardenburg's  point  is  well  taken.  It  is  a  fact  that 
most  of  the  experimental  work  that  has  been  done  on  size  of  seed 
piece  has  not  taken  into  account  a  study  of  the  most  economical 
distance  or  spacing  of  the  various  sizes  of  seed  pieces  in  the  row. 
There  is  no  question  but  that  much  of  the  apparent  superiority 
of  large  over  small  sizes  of  seed  pieces  has  been  due  to  the  fact 
that  the  spacing  of  the  pieces  in  the  row  have  more  nearly  ap- 
proached the  most  economical  distance  for  the  large  sized  seed 
piece  than  of  the  smaller  one.  For  example,  a  study  of  three  ounce 
whole  tubers  with  three  ounce  halved  tubers,  that  is  a  one  and  a 
half  ounce  seed  piece,  with  the  spacing  in  each  instance  sixteen 
inches  apart,  does  not  afi^ord  a  fair  basis  of  comparison ;  because 
it  is  altogether  probable  that  if  the  one  and  a  half  ounce  seed 
pieces  had  been  spaced  ten  or  twelve  inches  apart  their  total  yield 
would  have  been  much  greater  per  acre  than  at  sixtee*i  inches  apart. 


56 


PLANTING  METHODS 


On  the  other  hand,  it  is  altogether  likely  that  if  the  three-ounce 
whole  tubers  had  been  given  the  closer  spacing,  the  yield  of  market- 
able tubers  would  have  been  materially  decreased.  A  careful  study 
of  the  right  spacing  to  allow  for  different  sizes  of  seed  pieces  in 
order  to  secure  a  maximum  yield  of  marketable  tubers  is  needed 
for  each  of  the  leading  commercial  varieties,  in  order  to  furnish 
a  comparable  basis  for  the  determination  of  the  relative  value  of 
whole  vs.  cut  seed  or  large  vs.  small  seed,  regardless  of  whether  it 
is  whole  or  cut. 


Fir,.  2.")  — Socd-PuttiiiK  hopper-boxes  with  stationary  knives  greatly  farilitate  the  task 
of  preparing  the  seed  for  planting.     Courtesy  of  Daniel  Dean,  Nichols,  N.  Y. 

When  such  studies  have  been  made,  it  is  quite  likely  that  it  will 
be  found  that  too  large  or  too  small  seed  pieces,  whether  they  are 
whole  or  cut,  are  not  economical  to  use ;  and  that  the  most  desirable 
size  of  seed  piece  from  the  standpoint  of  net  marketable  yield  will 
involve  the  use  of  a  much  larger  quantity  of  seed  than  is  now 
ordinarily  employed. 

Influence  of  Season. — It  will  also  be  found  that  d liferent 
seasonal  conditions  favorably  or  adversely  affect  the"  results  secured 
from  different  sizes  of  pieces  even  with  proper  spacing.  For  ex- 
ample, maximum  results  from  whole  tubers  or  from  large  sizes  of 
cut  seed  can  only  be  secured  when  there  is  sufficient  available  plant 
food  and  moisture  in  the  soil  to  enable  the  plants  to  develop  the 
tubers  they  set  to  a  marketable  size.  It  is  also  equally  certain  that 
small  sizes  of  seed  pieces  are  more  likely  to  be  injured  by  unfavor- 
able soil  or  weather  conditions  after  planting.     If  the  soil  is  too 


SIZE  IN  IRRIGATED  REGIONS 


57 


dry,  many  of  the  seed  jjieces  will  fail  to  grow;  and  if  it  is  too 
wet  and  cold,  it  is  obvious  that  more  of  them  will  decay  than  of 
the  larger  sizes  of  seed  pieces,  particularly  if  whole  seed  has 
been  planted.  Xegleet  to  take  these  and  many  other  factors  into 
consideration  has  led  to  numerous  erroneous  conclusions  relative 
to  the  merits  of  large  and  small  sizes  of  seed  pieces. 

Size  in  Irrigated  Regions. — It  is  believed  that  in  the  irrigated 
regions  of  the  West,  where  it  is  possible  to  supply  the  necessary 


Fig.  26.— Cutting  with  stationary  knife.     The  cutting  edge  of  the  blade  should  face  in 
the  same  direction  as  the  operator.     Both  hands  are  free  to  handle  the  tuber. 

amount  of  moisture,  the  use  of  medium  sizes  of  whole  seed — say 
from  2  to  4  ounces  in  weight — of  such  varieties  as  the  Rural  New 
Yorker  No.  2  and  the  Eusset  Burbank,  will  give  better  results  than 
cut  seed.  There  is  reason  to  believe  that  in  the  case  of  the  Charles 
Downing  (Idaho  Eural)  the  use  of  whole  seed  will  be  found  un- 
desirable, on  account  of  its  habit  of  producing  more  stems  per  given 
weight  of  seed  piece  than  the  other  two  varieties,  and  also  to  its 
inherent  tendency  to  set  a  larger  number  of  tubers  per  stem.  It 
is  apparent,  therefore,  that  the  variety  itself  is  an  important  factor 
in  determining  the  best  size  of  seed  piece  to  use. 


58 


PLANTING  METHODS 


General  Practice  Regarding  Size. — Generally  speaking,  it  is 
advisable  to  use  a  liberal  size  of  seed  piece,  one  weighing  from  one 
and  a  fourth  to  two  ounces.  As  a  rule,  this  will  contain  from  one 
to  throe  eyes.  A  three-ounce  tuber  cut  in  two  or  a  four-ounce  cut 
into  three  pieces  has  given  very  satisfactory  results.  The  list  of 
references  on  size  of  seed  piece  to  use  is  by  no  means  a  complete 


Fig.  27. — A  set  of  adjustable  knives  fastened  in  a  frame  resting  on  a  slat  crate.  A  sharp 
blow  from  the  wooden  mallet  forces  the  tuber  through  thereby  dividing  it  as  many  times  as 
there  are  blade  sections  covered. 

one,  but  it  will  serve  to  show  the  amount  of  interest  shown  in 
this  subject. 

Cutting  the  Seed. — For  the  most  part,  seed  potatoes  are  cut 
by  hand  rather  than  Avith  automatic  cutters;  but  the  scarcity  and 
high  cost  of  labor  and  the  continual  improvement  of  automatic 
seed-cutting  implements  are  having  a  tendency  to  increase  their 
use,  even  though  they  are  not  as  satisfactory  as  hand  work.  Thus 
far,  no  automatic  seed-potato  cutter  has  been  devised  which  is  able 
to  distinguish  between  weak  and  strong  eyes  or  no  eyes  at  all; 
hence  there  is  bound  to  be  a  certain  percentage  of  seed  pieces  which 


WHEN  TO  CUT  SEED 


59 


will  not  produce  plants,  or  if  they  do,  they  will  be  weak.  On  the 
other  hand,  all  seed  pieces  that  have  been  carefully  cut  by  hand 
will  contain  one  or  more  strong  eyes  (Fig.  24). 

A  seed-cutting  box  or  hopper  such  as  that  shown  in  figure  25 
with  stationary  knife  blade,  or  without  the  hopper  as  shown  in 
figure  26,  greatly  mininiii^es  the  labor  of  cutting  seed.  The  home- 
made device  shown  in  figure  27,  if  used  by  a  careful  operator,  will 


Fio.  28. — An  8K  ounce  Green  Moun- 
tain tuber  before  cutting. 


Fig.  29. — First  step  in  cutting  the  8J<  ounce 
tuber.     Cut  from  seed  to  stem  end. 


give  a  low  percentage  of  eyeless  seed  pieces.  Figures  29  and  30 
illustrate  the  process  of  cutting  a  large  tuber  (Fig.  28)  into  single 
eye  pieces.  The  tuber  should  be  cut  so  as  to  make  blocky  rather 
than  wedge-shape  seed  pieces  ( Fig.  30 ) .  The  advantage  of  a  blocky 
seed  piece  is  that  it  is  handled  better  in  the  planter,  and  is  less 
likely  to  dry  out  or  to  decay  in  the  ground  if  the  weather  conditions 
are  unfavorable. 

When  to  Cut  Seed. — As  a  rule,  seed  potatoes  are  cut  about  as 
required  for  planting;  but  when  large  acreages  are  to  be  planted 
and  labor  is  scarce,  it  is  often  found  more  economical,  as  well  as 
more  convenient,  to  cut  the  seed  in  advance  of  the  planting  season. 
One  of  the  most  noted  examples  of  cutting  seed  considerably  in 


60 


PLANTING  METHODS 


advance  that  has  conio  to  the  writtr's  attention,  is  the  practice 
oi'  tlie  growers  in  the  Louisville,  Kentucky  district  of  cutting  their 
seed  potatoes,  during  December  and  January,  for  not  only  their 
spring  crop  but  the  fall  one  as  well.  In  other  words,  part  of  the 
December  and  January  cut  seed  is  planted  in  March  or  early  April, 
and  the  balance  used  for  the  second  or  fall  crop  in  July.     When 


Fig.  30. — Final  result  in  cutting  an  85-4  ounce  tuber  into  as  many  one-eye  seed  pieces 
ssible.     Pieces  at  seed  end  have  more  than  one  e.ve.      Note  blocky  shape  of  seed  pieces. 
Average  weight  of  pieces  is  54  of  an  ounce. 

the  seed  is  cut  considerably  in  advance  of  its  use,  care  must  be 
exercised  in  handling  the  freshly  cut  material  in  order  to  avoid 
injury  from  overheating  while  it  is  curing. 

Dusting  Freshly  Cut  Seed. — The  freshly  cut  seed  handles 
))etter  if  sprinkled  as  cut  with  land  plaster,  air-slaked  lime,  or 
flowers  of  sulfur.  These  materials  tend  to  dry  the  cut  surface, 
and  lessen  the  danger  from  heating  if  the  weather  is  warm  and 
the  seed  is  not  j)lanted  immediately. 

Treatment  of  Seed. — The  curing  or  drying  ])rocess  is  facili- 
tated by  the  use  of  one  of  the  a})Sorbents  mentioned,  and  then  plac- 
ing the  seed  in  slatted  crates  or  spreading  it  out,  in  a  thin  layer, 


RATE  AND  DISTANCE  OF  PLANTING  61 

on  the  floor  of  a  frost-proof  house,  if  in  the  winter  season,  turning 
it  over  once  or  twice  during  the  first  twenty-four  hours,  and  once 
during  each  of  the  following  two  days ;  after  which  the  cut  surfaces 
are  generally  dry  enough  to  permit  of  being  stored  in  barrels, 
sacks,  or  bins  until  needed  for  planting.  Some  growers  prefer  to 
handle  their  seed  in  this  manner  rather  than  to  cut  it  as  needed, 
claiming  that  they  obtain  much  better  results.  But,  whatever  the 
method  adopted,  the  important  thing  to  remember  is  that,  if  the 
weather  is  warm,  freshly  cut  seed  develops  heat  very  rapidly  and 
that,  under  these  conditions,  its  vitality  is  quickly  injured.  Many 
a  poor  stand  has  been  attributed  to  the  poor  quality  of  the  seed 
stock  or  to  the  imperfect  operation  of  the  planter  when,  in  reality, 
the  real  cause  was  due  to  impro])er  handling  of  the  cut  seed. 

Rate  and  Distance  of  Planting. — The  rate  or  distance  of 
planting  should  be  largely  governed  by  the  following  factors:  (1) 
the  variety  grown;  (2)  the  natural  normal  rainfall  of  the  section, 
and  the  moisture-holding  capacity  of  the  soil;  (3)  the  supply  of 
available  plant  food  it  contains;  and  (4)  the  size  of  the  seed  piece 
used.  In  some  sections  in  Europe  early  varieties  are  frequently 
planted  in  rows  24  inches  or  less  apart,  with  an  8-inch  to  12-inch 
spacing  in  the  row.  Similar  close  planting  was  noted  near 
Eimouski,  Province  of  Quebec,  Canada,  in  1918.  In  this  country  the 
rows  are  seldom  less  than  30  inches  apart  and  only  occasionally  at 
that  distance.  As  a  rule  such  varieties  as  Irish  Cobbler  and  Tri- 
umph are  spaced  from  32  to  34  inches  apart  and  from  8  to  12 
inches  apart  in  the  row. 

The  following  discussion  on  spacing  is  from  Farmers'  Bulle- 
tin 10G4^:  "In  x\roostook  County,  Maine,  early  varieties  such  as 
the  Irish  Cobbler,  Triumph,  and  Early  Rose  are  usually  planted 
in  rows  32  to  34  inches  apart  and  from  8  to  12  inches  apart  in 
the  row.  The  Green  Mountain,  which  is  the  leading  late  variety 
of  that  region,  is  planted  in  rows  from  34  to  36  inches  apart  and 
the  plants  in  the  row,  10  to  14  inches  apart,  depending  on  tlie  size 
of  the  seed  piece  used." 

The  table  in  Bulletin  1064,  shows  the  number  of  seed  pieces 
required  for  an  acre  when  planted  at  different  distances.  A  study 
of  the  data  presented  in  this  table  show  that  the  closest  spacing, 
30  by  8  inches,  would  require  26,136  seed  pieces  to  the  acre  as 
compared  with  14,520  for  a  spacing  of  36  by  12  inches,  which  is  the 
more  common   planting  practice.     The  wider  spacings  included 


62 


PLANTING  METHODS 


in  the  table  are  not  infrequently  encountered  in  the  dry-farming 
sections  of  the  West,  where  the  deficiency  in  moisture  makes  it 
impossible  to  grow  potatoes  successfully  at  the  distances  usual  in 
the  humid  areas  of  the  United  States. 

"A  comparison  of  the  two  extremes  in  spacing  shows  26,136 
seed  pieces  in  one  and  3,630  in  the  other,  the  ratio  between  the  two 
being  1  to  7.2;  in  other  words,  the  number  of  seed  pieces  required 
to  plant  an  acre  30  by  8  inches  apart  would  plant  7.2  acres  48 
by  36  inches  apart. 

Number  of  seed  pieces  required  to  plant  an  acre  of  potatoes  at  different 
spacings. 


Pieces  of  potato  seed  required  at  stated  spacing  distances  (number) 

apart 

8  inches 

10  inches 

12  inches 

14  inches 

16  inches 

18  inches 

24  inches^ 

36  inches 

30  inches 

26,136 

20,909 

17,424 

14,935 

13,068 

11,616 

8,712 

5,808 

32  inches 

24,502 

19,602 

16,335 

14,001 

12,251 

10,890 

8,168 

5,445 

34  inches 

23,061 

18,449 

15,374 

13,178 

11,531 

10,249 

7,687 

5,125 

30  inches 

21,780 

17,424 

14,520 

12,446 

10,890 

9,680 

7,260 

4,840 

42  inches 

18,669 

14,935 

12,446 

10,668 

9,334 

8,297 

6,223 

4,149 

48  inches 

16,335 

13,068 

10,890 

9,334 

8,168 

7,260    1     5,445 

3,630 

Amount  of  Seed  Required. — "The  number  of  bushels  of  seed 
employed  in  planting  an  acre  of  potatoes  varies  considerably  in 
different  parts  of  the  country.  Eoughly  stated,  the  quantity  actu- 
ally used  varies  from  5  to  18  bushels  per  acre.  The  average 
quantity  of  seed  planted  per  acre  in  the  United  States  was  estimated 
several  years  ago  by  the  Bureau  of  Crop  Estimates  at  8.6  bushels. 
As  a  rule,  the  smaller  quantities  are  used  by  the  southern  truck 
grower,  who  is  generally  obliged  to  pay  a  high  price  for  seed  stock 
on  account  of  his  distance  from  the  source  of  its  production  and 
the  season  of  the  year  at  which  he  has  to  have  it  delivered.  In 
Aroostook  County,  Me.,  the  common  practice  is  to  plant  from  5 
to  6  barrels  of  seed  per  acre,  or  from  825  to  990  pounds  (13.7  to 
16.5  bushels). 

In  order  to  afford  a  ready  reference  to  the  actual  quantity  of  seed 
required  to  plant  an  acre  with  seed  pieces  of  definite  weights  at  a 
given  distance  between  plants,  the  next  table  has  been  prepared  to 
cover  seed  pieces  ranging  from  half  an  ounce  to  two  ounces  in 
weight.  It  will  be  noted  that  plantings  made  at  close  intervals 
with  seed  pieces  ranging  from  one  and  a  quarter  to  two  ounces 


AMOUNT  OF  SEED  REQUIRED 


63 


Number  of  bushels  of  potatoes  required  to  plant  an  acre  at  different 
spacings  with  seed  prices  of  various  sizes. 


Spacing  of  rows  and 
seed  pieces 

Rows  30  inches  apart: 

8-inch  spacing. . . 

10-inch  spacing.  . 

12-inch  spacing. 

14-inch  iipaeing. .  . 

16-inch  spacing..  . 

18-inch  spacing... 

24-inch  spacing.. 

36-inch  spacing..  ■ 

Rows  32  inches  apart: 

S-inch  spacing. . . 

10-inch  spacing..  . 

12-inch  spacing..  . 

14-inch  spacing..  . 

16-inch  spacing. .  . 

18-inch  spacing..  . 

24-inch  spacing. .  . 

36-inch  spacing. . 
Rows  34  inches  apart: 
8-inch  spacing.  .  . 

10-inch  spacing.  . . 

12-inch  spacing. .  . 

14-inch  spacing.. . 

16-inch  spacing.. . 

IS-inch  spacing. .  . 

24-inch  spacing. .  . 

36-inch  spacing.. . 

Rows  36  inches  apart: 

8-inch  spacing. .  . 

10-inch  spacing. .  . 

12-inch  spacing..  . 

14-inch  spacing..  . 

16-inch  spacing..  . 

IS-inch  spacing.. . 

24-inch  spacing..  . 

36-inch  spacing..  . 
Rows  42  inches  apart: 

18-inch  spacing..  . 

24-inch  spacing. . . 

30-inch  spacing.. . 

36-inch  spacing. .  . 
Rows  48  inches  apart: 

IS-inch  spacing. 

24-inch  spacing 

30-inch  spacing 

36-inch  spacing. 


Seed  requ 

ired,  the  average  we 

ight  of  see 

1  pieces  us 

ed  being  as 

(bushels) 

J  2  ounce 

%  ounce 

1  ounce 

l^iozs. 

l>^ozs. 

13^  ozs. 

13. G 

20.4 

27.2 

34.0 

40.S 

47.6 

10.9 

16.3 

21.8 

27.3 

32.6 

38.1 

9.1 

13.6 

18.2 

22.7 

27.2 

31.8 

7.S 

11.7 

15.6 

19.4 

23.3 

27.2 

6.8 

10.2 

13.6 

17.0 

20.4 

23.8 

6.0 

9.1 

12.1 

15.1 

18.2 

21.2 

4.5 

6.8 

9.1 

11.3 

13.6 

15.9 

3.0 

4.5 

6.0 

7.5 

9.1 

10.6 

12. S 

19.1 

25.5 

31.9 

38.3 

44.7 

10.2 

15.3 

20.1 

25.5 

30.6 

35.7 

8.5 

12.8 

17.0 

21.3 

25.6 

29.8 

7.3 

10.9 

14.6 

18.2 

21.9 

25.5 

6.4 

9.6 

12.8 

16.0 

19.2 

22.4 

5.7 

8.5 

11.3 

14.2 

17.0 

19.8 

4.3 

6.4 

8.5 

10.6 

12.7 

14.9 

2.8 

4.2 

5.7 

7.1 

8.5 

9.9      . 

12.0 

18.0 

24.0 

30.0 

36.0 

42.0 

9.6 

14.4 

19.2 

24.0 

28.3 

33.6 

8.0 

12.0 

16.0 

20.0 

24.0 

28.0 

6.9 

10.3 

13.7 

17.1 

20.6 

24.0 

6.0 

9.0 

12.0 

15.0 

IS.O 

21.0 

5.3 

8.0 

10.7 

13.3 

16.0 

18.7 

4.0 

6.0 

8.0 

10.0 

12.0 

14.0 

2.5 

3.8 

5.0 

6.3 

7.6 

8.8 

11.3 

17.0 

22.7 

28.4 

34.0 

39.7 

9.1 

13.6 

18.1 

22.7 

27.2 

31.7 

7.6 

11.3 

15.1 

18.9 

22.7 

26.5 

6.5 

9.7 

13.0 

16.2 

19.4 

22.7 

5.7 

8.5 

11.3 

14.2 

17.0 

19.8 

5.0 

7.6 

10.1 

12.6 

15.1 

17.6 

3.8 

5.7 

7.0 

9.5 

11.3 

13.2 

2.5 

3.8 

5.0 

6.3 

7.6 

8.8 

4.3 

6.5 

8.6 

10.8 

13.0 

15.1 

3.2 

4.9 

6.5 

8.1 

9.7 

11.3 

2.6 

3.9 

5.2 

6.5 

7.8 

9.1 

2.2 

3.2 

4.3 

5.4 

6.5 

7.6 

3.8 

5.7 

7.6 

9.5 

11.3 

13.2 

2.8 

4.2 

5.7 

7.1 

8.5 

9.9 

2.3 

3.4 

4.5 

5.7 

6.8 

7.9 

1.9 

2.8 

3.8 

1 

4.7 

').7 

6.6 

64 


PLANTING  METHODS 


require  quantities  of  seed  very  greatly  in  excess  of  those  ordinarily 
used.  On  land  Avell  supplied  with  organic  matter,  an  abundant 
supply  ol'  available  plant  i'ood,  and  moisture,  the  use  of  large-sized 
pieces  or  whole  tubers  from  one  and  a  half  to  two  ounces  in  weight 
will  usually  prove  a  pro(ital)le  investment. 

"A  safe  general  rule  to  follow  in  planting  potatoes  is  to  in- 
crease or  decrease  the  distance  between  the  rows,  as  well  as  the 
hills,  in  accordance  with  the  size  of  the  seed  piece  used,  the  variety 
grown,  the  fertility  of  the  soil,  its  moisture-holding  capacity,  and 
the  average  normal  rainfall  that  may  be  expected  when  the  plants 
are  developing  their  tubers.  The 
nearer  the  soil  and  weather  condi- 
tions approach  the  ideal,  the  larger 
the  seed  piece  and  the  closer  the 
l)lanting.  Early-maturing  varieties 
may  be  planted  more  closely  than 
the  late-maturing  sorts,  because  the 
plants,  as  a  rule,  do  not  grow 
as  large. 

"A  study  of  the  talde  discloses  the 
fact  that  the  quantity  of  seed  re- 
quired for  planting  an  acre  of  pota- 
toes with  3-ounce  pieces  at  a  spacing 
of  30  by  8  inches  is  more  than  54 
bushels.  When  the  spacing  in  the 
row  is  doubled,  that  is,  made  30 
by  IG  inches,  only  one-half  this 
It  is  believed  that  when  seed  pieces 
averaging  2  ounces  in  weight  are  used,  a  spacing  of  13  to  14  inches 
may  be  expected  to  give  better  results  than  10  to  13  inches.  In 
other  words,  tlie  spacing  of  the  plants  in  the  row  is  to  a  large  extent 
governed  by  the  size  of  the  seed  piece  used," 

Planting  Methods. — The  seed  jneces  may  be  either  planted  by 
hand  or  with  a  machine.  In  the  South,  where  hand  planting  is 
more  generally  practised  than  in  the  North,  the  usual  practice  is 
to  open  up  a  furrow  with  a  one  or  two-horse  plow  or  middle  buster, 
distribute  and  mix  the  fertilizer  in  the  furroAV,  then  drop  the  seed 
by  hand  (Fig.  31)  and  cover  it  with  a  ])low.  In  the  tule  lands  of 
the  delta  sections  of  tlie  Han  Joaquin  and  Sacramento  rivers  near 
Stockton,  California,  seed  is  dropped  ]jy  band  in  every  oilier  furrow 


Fig.  31. — The  old  time  way 
planting  potatoes.    Portsmouth,  Va. 

quantity  will  be  required. 


TYPES  OF  PLANTERS 


65 


■■if^"*|P 


as  the  land  is  being  plowed;  while  in  certain  parts  of  Michigan  and 
Wisconsin,  and  probably  other  middle  western  states,  some  growers 
mark  their  land  in  both  directions  with  a  sled  or  other  horse-drawn 
marker  and  then  plant  and  cover  the  seed  with  a  hand  potato 
planter  (Fig.  32).  It  should  be  stated  that  in  some  New  England 
sections  where  but  small  acreages  are  grown  the  seed  is  dropped 
in  open  furrows  in  much  the  same  manner  as  in  the  South. 

Types  of  Planters. — Horse  drawn  machine  planters  are  of  two 
general  types,  viz.,  the  one-man  or  picker  (Fig.  33),  and  the  two- 
man  type  (Fig.  34).  In  the  former,  the  seed  pieces  are  picked  up 
by  forks  attached  to  a  re- 
volving vertical  disk  which 
passes  through  a  comi)art- 
ment  containing  the  cut 
seed.  The  seed  piece  thus 
])icked  up  by  each  fork  is 
stripped  off  as  it  passes 
between  two  finger-like 
attachments  and  falls  into 
the  dropping  tube.  Accu- 
racy in  planting  is  largely 
dependent  on  the  uniform- 
ity in  size  and  shape  of  the 
seed  pieces.  Blocky  shaped 
pieces  are  much  more  sat- 
isfactorily handled  than 
wedge-shaped  ones. 

The  Two-Man  Macliine. — In  the  operation  of  the  two-man 
planter  the  seed  pieces,  in  one  type,  are  raised  singly  from  the 
hopper  by  a  revolving  cogged  wheel  set  at  an  angle,  and  deposited 
in  the  pockets  of  a  horizontally  moving  disk,  which  discharges  the 
seed  piece  from  each  pocket  as  it  passes  over  the  dropping  tube. 
The  accuracy  of  this  machine  is  dependent  upon  the  ability  of  the 
second  man,  who  sits  in  the  rear,  to  see  that  each  pocket  has  a  seed 
piece  and  to  remove  any  extra  pieces  that  may  be  in  others  (Fig. 
34).  With  a  good  man  in  the  rear  this  machine  will  plant  100 
per  cent  perfect;  whereas  with  the  picker  type,  if  a  fork  failed  to 
get  a  seed  piece  in  its  revolution  through  the  supply  chamber,  or 
another  fork  spears  two  or  more  pieces,  there  is  no  one  to  correct 
these  mechanical  errors. 
5 


66 


PLANTING  METHODS 


The  Picker  Planter. — The  advantages  of  the  picker  type  of 
planter  are:  (1)  that  it  onl}-  requires  one  man  to  operate  it;  (2) 
that,  on  account  of  its  automatic  distribution  of  the  seed,  it  is 
possible  to  drive  the  horses  somewhat  faster,  thereby  planting  a 
larger  acreage  per  day.  Its  disadvantage  is  that  there  is  no  one 
to  correct  the  mechanical  errors,  such  as  have  been  previ- 
ously mentioned. 


■■r— J 

^^ 

t  ^r^ 

^^K       m 

M  ^^.(imA 

: .    n    ^ 

I      ■'"*  ■■ 

j^^^BW'  .> 

■/"  -^  y^-^i 

OiS 

^K..-  '-^ 

W\  ...l^jPi 

... . 

■  ■ 

^^^?^^^- 

-^^ 

K  ;^f 

Fig.  33. — A  2-row  picker  type  of  planter. 


The  Two  Machines  Compared. — Many  growers  feel  that  the 
slight  inaccuracies  of  the  picker  planter  are  not  of  sufficient  con- 
sequence to  justify  the  additional  cost  of  operating  a  two-man 
planter.  Assuming  that  the  picker  type  of  planter  drops  the  seed 
pieces  95  per  cent  perfect  and  that,  as  a  result,  the  yield  is  cut,  we 
will  say  3  per  cent,  is  this  amount  sufficient  to  pay  for  the  extra 
man  ?  The  answer  to  such  an  inquiry  is  dependent  upon  two 
factors,  (a)  the  yield  produced;  and  (b)  the  price  received  for  the 


TYPES  OF  PLANTERS 


67 


crop.  With  a  Iiundred  bushel  yiekl  and  a  value  of  $1.00  per 
bushel,  the  net  increase  would  be  $3.00.  As  a  two-man  planter 
should  average  under  fair  working  conditions  about  4  acres  per 
day,  this  would  mean  with  present  prices  of  labor  from  75  cents 
to  $1.00  extra  cost  per  acre,  but  as  the  picker  planter  will  plant, 
on  an  average,  more  land  per  day  than  the  two-man  planter,  a 
further  charge  should  be  made  against  the  latter.     In  the  planting 


Fig.  34. — Two-man  type  of  planters.    Courtesy  of  Bateman  Mfg.  Co.,  Grenloch,  N.  J. 


of  a  20-acre  field  of  potatoes,  let  us  assume  that  it  required  4  days 
for  the  job  with  a  picker  planter  and  5  days  with  a  two-man  planter, 
and  that  the  cost  of  operating  the  one  is  $7.00  per  day  and  $10.00 
for  the  other.  On  this  basis,  the  actual  cost  of  planting  an  acre 
of  potatoes  with  the  picker  type  is  $1.40,  as  against  $2.50  for  the 
two-man  planter,  or  a  difference  of  $1.10  per  acre  as  an  offset 
against  the  3  bushel  increase  in  yield. 

It  must  be  conceded,  however,  that  100  bushels  per  acre  is  rather 
a  low  yield,  and  that  a  95  per  cent  stand  is  probably  too  high  to 
represent  a  fair  average.     Suppose  a  yield  of  200,  300,  or  400 


68 


PLANTING  METHODS 


biishels  were  obtained  I'roin  the  ])i(ker-planted  field;  the  profits 
I'rom  the  use  oi'  the  extra  man  are  at  once  more  than  doubled, 
trebled,  or  quadrupled  because  the  initial  cost  of  planting  remains 
the  same ;  and  the  only  additional  cost  is  in  the  gathering,  hauling 
and  marketing  of  the  extra  bushels.  Many  fields,  however,  will 
not  show  over  90  per  cent  stand,  and,  if  the  seed  is  not  fairly 
uniform  in  size  and  shape,  the  percentage  of  stand  may  be  even 


Fig.  35. — A  good  stand  of  Irish  Cobbler  potatoes.    Aroostook  County,  Me.,  1914. 


less  than  this ;  thus  we  ma}'  have  a  much  larger  jjcrcentage  of 
increase.  In  explanation  of  the  calculation  of  a  3  per  cent  gain, 
instead  of  5  per  cent  on  a  95  per  cent  stand,  it  should  be 
stated  that  plants  adjacent  to  missing  hills  give  an  increased 
yield;  it  has  therefore  been  thought  desirable  to  only  claim  a  60 
per  cent  increase  or  3  instead  of  5  per  cent. 

A  Perfect  Stand  Desired, — The  main,  outstanding  object  for 
which  the  grower  should  strive  is  that  of  securing  as  nearly  a  perfect 
stand  as  it  is  possible  to  secure  (Fig.  35).     Maximum  yields  cannot 


EFFECT  OF  BAD  HANDLING  OF  SEED  69 

be  produced  when  there  is  a  large  percentage  of  missing  plants 
(Fig.  oG).  Carelessl}"  cut  seed  ])ieces,  improperly  handled  seed 
or  an  imperfect  phuiting  machine  all  tend  to  reduce  yield. 

Effect  of  Bad  Handling  of  Seed. — Poor  seed  is  often  the 
result  of  injuries  to  the  tubers  through  rough  handling.  The  prac- 
tice of  many  seedsmen  of  shipping  seed  to  their  customers  in  sacks, 
instead  of  heavy  pasteboard  or  wooden  packages,  is  often  responsible 
for  much  injury.  This  is  Avell  illustrated  in  figures  37  to  39,  in 
which  a  sack  and  a  pasteboard  container  are  shown  as  is  also  the 


Fig.  30. —  A  poor  stand  of  potatoes  due  in  large  part  to  poor  seed.      Jerome,  Ida. 


condition  of  the  stock  as  received  from  the  express  company.  The 
reader  can  readily  draw  his  own  conclusions  regarding  the  desira- 
bility of  the  two  lots  of  seed. 

There  is  every  reason  to  believe  that  the  same  relative  difference 
in  the  condition  of  the  seed  would  have  been  noted  if  the  shipment 
had  been  made  by  parcel  post. 

QUESTIONS    ON    THE   TEXT 

1.  Is  adaptation  an   important  consideration   in  the   selection   of  a  vari- 

ety ?     Why  ? 

2.  What  is  said  regarding  the  Brown  Beauty?     Where  is   it  grown? 
ti.  Where  is  the  White  Rose  grown? 

4,  Of  what  importance  is  good  seed?     Define  good  seed. 

5.  Is  it  desirable  to  plant  the  cull  stock?     Give  reasons. 


70 


PLANTING  METHODS 


a>  a 


PLANTING  METHODS 


71 


72  QUESTIONS  SUGGESTED  BY  THE  TEXT 

6.  How  nearly  does  the  certified  seed  now  produced  supply  the  demand. 

7.  Describe   the   method    of   greening   or   germinating   seed   tubers.     Give 

object. 

8.  To  what  extent  has  the  question  of  size  of  seed  pieces  been  studied? 
!).  Is  whole  seed  superior  to  cut  seed?     Can  you  give  a  reason? 

10.  What  should  constitute  a  fair  basis  of  comparison  as  to  the  relative 

merits  of  different  sizes  of  seed  pieces? 

11.  What  relation  does  the  supply  of  plant  food  and  moisture  have  to  size 

of  seed  piece? 

12.  Where    and    under    A\hat    conditions    may    whole    tiiliors    be    used    for 

seed  purposes? 

13.  Why  is  the  Charles  Downing  unsuited  for  planting  whole? 

14.  How  are  seed  potatoes  usually  cut? 

1.").   Should  automatic  cutters  ))e  used?     Why? 

Ifi.  With  what  is  it  desirable  to  dust  freshly  cut  seed,  as  an  absorbent? 

17.  How  should  the  cut  seed  be  treated  to  preserve  its  vitality? 

18.  What  factors  should  govern   the  rate  or  distance  of  planting? 
10.  What  is  the  usual  spacing  in  the  United  States? 

20.  At    what    distance    are    Irish    Cobblers    and    Triumphs    usually    spaced 

in   Maine? 

21.  What  difference  is  noted  for  the  Green  Jlountain? 

22.  How  many  seed  pieces  would  it  require  to  plant  an  acre  if  they  were 

spaced  30  by  8  inches  apart? 

23.  Wliere  are  the  wider  spacings  practised?     Why? 

24.  How    many    acres   would    the    seed    required    for    the    closest    spacing 

plant  if  used  at  the  widest  spacing? 

25.  What  is  the  average  amount  of  seed  used  per  acre  in  the  United  States? 

26.  What  is  the  average  amount  used  per  acre  in  ]Maine? 

27.  How  is  the  seed  usually  planted? 

28.  In   what   sections   of  the   country   is   hand   planting   still   very   largely 

practised  ? 
20.  Into  what  two  classes  or  types  are  horse  drawn  planters  divided? 

30.  Describe  the  mechanical  operation  of  the  picker  type  of  planter.     Give 

advantages  and  disadvantages. 

31.  Describe  the  operation  of  the  two-man  planter. 

32.  What  is  the  approximate  cost  of  planting  an  acre  of  potatoes  with  a 

one-row  picker  machine?     With  a  two-man   type  of  planter? 

33.  What   is   the   main   outstanding   object   for    which    the   grower    should 

strive   in   planting  his  crop?     How   secured? 


QUESTIONS   SUGGESTED  BY  THE  TEXT 

1.  What  varieties  of  potatoes  are  used  for  early  planting  in  your  region? 

2.  What  ones  are  used  for  late  planting? 

3.  What  are  the  sources  of  these  seed  potatoes? 

4.  Is   careful    selection   practised   by   local   growers?      Or   are   culls    used 

by  some  for  planting? 

5.  To   what    extent   are   greening   and    sprouting   practised    locally?      For 

which  crop? 

6.  Give  the  local  practices  regarding  sizes  of  seed  pieces  and  methods  of 

cutting  and  treating  seed. 


REFERENCES  CITED  73 

7.  What  are  the  common  local  methods  of  planting?     Give  the  distances? 

8.  What  types  of  machine  planters  have  you  observed?     What  results? 

9.  What  stands  have  you  observed?     Give  percentages  for  best  and  poorest. 
10.  Assign  some  of  your  relasons  for  poor  stands  observed. 

References   Cited 

1.  Anonymous.     1908.     Field  Experiments.     Jour.  Dept.  Agr.  and  Tech. 

htstr.  Ireland.  8:   296-297.  1908. 

2.  Greig,  R.   B.      1906.     The  sprouting  of   seed   potatoes.     Aberdeen  and 

No.  of  Scot.  Coll.  of  Agr.  Bui.  3:9,  1906. 

3.  HardenburCx,    E.    V.    1920.     Cutting    seed    potatoes.     The    Pot.    Mag. 

2:6,  March,  1920. 

4.  Stuart,  W.     1919.     Production  of  late  or  main  crop  potatoes.     U.  S. 

Dept.  Agr.  Farmers'  Bui.   1064:   22-25,  1919. 


CHAPTEK  VIII 
THE  CULTURAL  CARE  OF  THE  GROWING  CROP 

Systems  of  Culture. — There  are  two  well  recognized  systems 
of  potato  culture  in  the  Ignited  States  commonly  known  as  the 
ridge  and  level  culture  methods.  In  the  choice  of  either  of  tlu; 
systems  the  grower  should  he  guided  hy  his  own  environ- 
mental conditions. 

Ridge  Culture. — In  the  ridge  culture  method,  the  soil  between 
the  rows  is  loosened  hy  some  tillage  implement,  usually  a  riding 
cultivator  (Fig.  40),  and  is  then  drawn  or  thrown  uj)  over  or 
around  the  i)lants  by  a  winged  or  disk  horse-hoe  (Fig.  41).    In  the 


Fig.  40 — '1  In  laim  .~.i.-  .  .  .- ni<l  brtween  the  rows  with  a  ridiim  ,  ,iii  ,\  .,i,.i ,  ,ii  ii_i 
which  it  is  moulded  ovu  the  pLuito,  btloiu  they  have  pushed  through  the  surfaee,  with  a 
2-row  winged  horse-hoe. 

earlier  stages  of  cultivation  this  process  virtually  consists  in  a 
tearing  down  and  building  up  process.  The  ridge  culture  method 
is  very  generally  practised  in  Maine,  portions  of  New  York  and 
New  Jersey,  in  the  South,  and  in  the  irrigated  regions  of  the  West, 
with  the  exception  of  the  Delta  lands  in  the  Stockton,  California, 
district  and  the  Clatskanie  section  in  Oregon.  Outside  of  the 
irrigated  districts  its  practice  is  generally  confined  to  regions  wliere 
the  rainfall  is  ample  during  the  growing  season,  and  also  where 
high  summer  temperatures  are  not  likely  to  occur. 
74 


TILLAGE 


75 


Level  Culture. — The  level  culture  method  implies  a  system  of 
tillage  that  leaves  the  laud  practically  level  after  each  cultivation. 
As  a  rule  most  growers,  at  the  last  cultivation,  adjust  the  cultivator 
teeth  or  shovels  so  as  to  throw  the  soil  towards  the  plants.  This 
is  done  to  protect  the  tubers  that  are  developing  ne^r  the  surface 
from  being  sunburned. 

The  system  of  culture  to  be  practised  should  in  a  large  measure, 
determine  the  depth  at  which  the  seed  should  be  ])lanted.     In 


Fig.  41. — ^A  riding  2-row  disk  horse-hoe  ridging  or  mouldinK  the 
This  implement  requires  only  one  man  to  operate  it. 


the  plants. 


level  culture  the  seed  piece  should  be  planted  deeper  than  in  the 
ridge  method.  The  deeper  ])lanting  is  necessary  in  order  to  pro- 
tect the  new  tubers  from  light  and  sun  heat,  due  to  their  formation 
too  near  the  surface  if  planted  sli allow. 

Tillage. — The  term  tillage,  as  herein  used,  relates  solely  to  the 
cultivation  of  the  crop  after  it  is  planted.  The  object  of  tillage 
is  to  stimulate  the  growth  of  the  crop  planted  by  destroying  weeds 
and  keeping  the  soil  loose  and  friable.  This,  in  turn,  conserves 
moisture,  aerates  and  sweetens  the  soil,  and  favors  the  growth 
of  micro-organisms  that  aid  in  the  decomposition  of  organic  matter, 
as  well  as  those  that  are  concerned  in  the  production  of  nitrate 
nitrogen.  The  more  finely  divided  the  soil  particles  are,  the  larger 
will  be  the  amount  of  food  made  available  to  the  plant.     Good 


76       CULTURAL  CARE  OF  THE  GROWING  CROP 

tillage,  tlioreforc,  iiiiplits  caily,  ri'oqueiit,  careful,  and  thorough 
cultivation  oi'  the  croj),  up  to  that  stage  of  its  growth  when 
the  injury  to  its  root  system  is  greater  than  the  other  benefits 
accruing  therefrom.  When  this  stage  is  reached  tillage  should 
be  discontinued. 

Pre-Germimition   Tilhir/e. — The  importance  of  cultivating  the 
crop    before    the    plants    a])pear    above    ground    cannot    be    over- 


FiG.  42. — Pre-germination  tillage  of  thr  potato  crop  with  a  weeder.    Weed  seeds  may 
germinate  but  the  seedlings  are  unable  to  establish  themselves  under  this  system  of  culture. 
Courtesy  of  the  Bateman  Manufacturing  Co. 

emphasized.  The  old  practice^  and  one  too  frequently  followed 
today,  of  allowing  the  crop  to  care  for  itself  until  the  potato  plants 
have  appeared  above  ground  in  sufficient  numbers  to  define  the 
rows,  is  not  to  be  recommended  as  an  up-to-date  method. 

The  implements  commonly  employed  in  pre-germination  tillage 
when  the  level  culture  method  is  followed,  are  the  spike-tooth  or 
smoothing  harrow,  and  tlie  M-eeder  (Fig.  43).  Tillage  with  either  of 
these  implements  is  usually  done  by  going  lengthwise  of  the  rows. 
The  object  of  this  early  tillage  is  to  maintain  a  surface  soil  mulch, 
thus  conserving  the  moisture,  and  also  to  destroy  germinating  weed 
seeds.     The  significance  of  weed  destruction  at  this  early  stage  in 


PRE-GERMINATION  TILLAGE  77 

tlieir  growth,  before  they  have  become  deep-rooted,  can  be  best 
understood  by  the  statement  that  it  frequently  means  the  possi- 
bility of  avoiding  the  necessity  of  hand-hoeing  the  crop  later  on. 
Cultivation  with  either  or  both  of  these  implements  may  be  con- 
tinued without  injury  to  the  plants  until  they  are  well  above  ground, 
provided  the  teeth  of  the  smoothing  harrow  are  slanted  backward 
so  as  to  prevent  deej)  penetration  of  the  soil,  with  consequent 
injury  to  the  potato  stems.  From  one  to  two  cultivations  of  this 
character  are  ordinarily  sufficient,  but,  if  frequent  heavy  rains 
occur  during  this  period  additional  ones  may  be  necessary. 


Fig.  43. — Deep  tillage  between  the  rows  prior  to  the  appearance  of  the  plants  above  ground. 

The  foregoing  discussion  of  pre-germination  tillage  or  cultiva- 
tion applies  to  a  large  percentage  of  the  potato  acreage  of  the 
United  States,  but  not  to  all  of  it.  Aroostook  County,  Maine, 
furnishes  a  notable  example  of  another  type  of  i)re-germination 
tillage.  In  this  locality  the  growers  practise  the  ridge  system  of 
culture;  coupled  with  it  they  have  adopted  the  method  of 
moulding  the  soil  over  the  plants  prior  to  their  appearance  above 
ground.  The  grower,  in  this  case,  may  entirely  dispense  with 
the  spike-tooth  harrow  and  the  weeder;  or  he  may  use  them  once 
before  beginning  to  mould  or  ridge  the  soil  over  the  seed  pieces. 
The  course  usually  pursued  is  to  cultivate  the  soil  as  deeply  as 
practicable  between  the  rows,  and  then  follow  this  operation  with 


78       CULTURAL  CARE  OF  THE  GROWING  CROP 

a  wing  or  disk  i)otato  hoe  which  draws  or  throws  the  soil  over 
the  row.  In  this  section  where  i)otato  growing  is  conducted  on 
such  a  hirge  scale,  one  seldom  sees  a  one-horse  cultivator,  except  in 
one  of  the  final  operations  in  which  a  one-horse  potato  hiller  or 
wing  shovel  plow  is  used.  The  two-horse  riding  cultivator  is  used 
in  loosening  up  the  soil  (Fig.  43)  and  a  one-row  or  two-row 
walking  or  riding  wing  or  disk  potato  hoc  follows  and  ridges  it  up 
over  the  plants  (Figs.  40  and  41).    This  operation  may  be  repeated 


Fig.  44. — Normal  height  of  ridges  in  Aroostook  County,  Me. 

before  the  plants  are  finally  alloM^ed  to  break  ground.  This  type 
of  tillage  is  just  as  effective,  if  not  more  so,  in  the  control  of  weed 
growth  and  the  conservation  of  soil  moisture,  as  is  the  harrow  or 
the  weeder.     The  height  of  the  ridges  is  shown  in  figure  44. 

Tillage  after  Germination. — In  the  level  culture  method, 
potato  growers  are  generally  agreed  that  the  first  cultivation  of 
the  crop  after  the  plants  appear  above  ground  should  be  as  deep 
and  as  close  to  the  plants  as  it  is  possible  to  go.  The  two-horse 
riding  cultivator  is  almost  universally  used  in  the  northern  com- 
mercial potato-producing  sections  (Fig.  45).  In  the  South  various 
implements  including  the  riding  cultivator  are  in  use.  The  ten- 
dency however  has  been  toward  one-horse  implements.  A  small 
one-horse  turning  plow  is  one  of  the  implements  commonly  used 


TILLAGE  AFTER  GERMINATION 


79 


by  the  southern  truck  grower  in  the  cultivation  of  hoed  crops, 
including  the  potato.  Cultivation  with  the  plow  consists  in  throw- 
ing a  light  furrow  away  from  the  plants  or  toward  them  as  the  case 
may  be,  the  object  presumahly  being  to  bury  weeds  and  loosen  up 
the  soil.  The  advisability  of  plowing  a  furrow  away  from  the  plants 
on  each  side  of  the  row,  leaving  a  narrow  ridge  of  land,  six  to 


>^>3S^ 


Fig.  45. — First  cultivation  with  the  riding  cultivator.  Prior  to  this  the  surface  of  the 
ground  was  kept  loose  and  the  weeds  destroyed  by  the  use  of  the  wecder  or  spike-tooth 
harrow.  This  field  is  being  grown  under  the  level  culture  system.  Courtesy  of  the  Bateman 
Manufacturing  Co. 

eight  inches  in  width,  standing  uj)  four  or  five  inches  above  the 
bottom  of  the  furrow  exposed  to  the  drying  eifects  of  the  sun  and 
wind,  will  hardly  appeal  to  the  reader  as  a  sane  cultural  operation. 
If  the  object  of  such  practice  was  to  root-prune  and  check  the 
growth  of  the  potato  plants,  it  might  be  regarded  as  a  very  com- 
mendal)le  procedure;  but  as  a  stimulant  to  plant  growth  it  should 
be  classed  as  a  highly  undesirable  cultural  operation.  The  one- 
horse  cultivator,  when  proi)erly  uged,  is  just  as  effective  an  imple- 


80 


CULTURAL  CARE  OF  THE  GROWING  CROP 


raent  in  loosening  up  the  soil  as  the  riding  cultivator.  In  the 
level  culture  metliod  little,  if  any,  soil  is  thrown  toward  the  plants 
until  the  final  cultivation,  when  the  outside  shovels  or  cultivator 
teeth  are  set  at  an  angle,  so  as  to  throw  some  soil  toward  the  row. 
Tlie  number  of  cultivations  that  sliouhl  he  given  is  largely  depen- 


FiG.  46. — The  last  cultivation  with  the  riding  cultivator.  After  this  the  injury  to  the 
root  system  of  the  plant  is  normally  greater  than  the  benefits  derived  from  loosening  the  soil. 
Courtesy  of  the  Bateman  Manufacturing  Co. 

dent  on  the  character  of  the  season  and  the  soil.  A  safe  general 
rule  to  follow  is  to  till  the  crop  as  often  as  may  be  necessary  to 
keep  the  surface  loose  and  friable.  This  may  be  3,  4,  5,  6,  or 
more  times. 

After  the  first  deep  cultivation,  tlie  subsequent  ones  should 
be  shallower  and  shallower  and  further  and  further  away  from  the 
plants.     The  aim  should  be  to  cultivate  as  much  of  the  intervening 


HAND  HOEING 


81 


space  between  the  rows  as  possible,  witliout  causing  material  injury 
to  the  roots  of  the  plants. 

Cultivation  Avith  level  culture  should  cease  when  the  plants  are 
in  blooni^  or  when  the  tubers  get  as  large  as  a  hen's  egg.  When- 
ever the  root  pruning  becomes  severe  cultivation  should  cease. 

In  the  case  of  ridge  culture,  cultivation  may  be  continued  a 
little  later,  because  the  roots  of  the  plants  are  largely  confined  to 
the  soil  in  the  ridge,  and  the  slight  amount  of  tillage  that  is  possible 


Fig.  47. — A  4-inch  artesian  well  near  Palatka,  Fla.    Note  volume  and  rate  of  flow. 

in  the  centre  of  the  row,  does  little  if  any  injury.  As  a  rule 
cultivation  should  cease  when  the  plants  are  in  full  bloom  or  just 
passing  out  of  it  (Fig.  46). 

Hand  Hoeing. — In  commercial  potato-producing  sections  the 
crop  is  seldom  hoed  more  than  once ;  and  in  soil  specially  free  from 
weeds,  the  hoe  may  not  be  used  at  all.  Where  potato  growing  is 
not  strictly  a  commercial  business,  considerable  hand  hoeing  is 
frequently  done.  Hand  hoeing  should,  however,  be  regarded  as 
too  expensive  a  tillage  practice  to  justify  its  extensive  use.  The 
grower  should  endeavor  to  destroy  the  most  of  the  weeds  in  the 


82 


CULTURAL  CARE  OF  GROWING  CROP 


earlier  stages  of  cultivation.  In  some  sections,  as  in  portions  of 
Michigan  and  Wisconsin,  the  grower  attempts  to  dispense  with 
hand  labor  by  check-rowing  the  tield,  so  as  to  permit  of  cultivating 
the  crop  in  both  directions ;  but  such  wide  spacing  reduces  the  yield 
per  acre  and  is  not  to  be  commended. 

Special  Cultural  Features. — In  the  various  production  centres 
of  the  United  States  certain  cultural  practices  are  in  vogue  that 
are  both  interesting  and  instructive  to  those  residing  in  other 
sections  of  the  country.     The  Hastings  district  in  Florida,  for  ex- 


FiG.  4S. — One  row  omitted  between  raised  beds  for  irrigation  furrow- 
ample,  is  of  interest  from  the  standpoint  of  its  irrigation  practice 
and  system  of  growing  the  potato  crop  on  raised  beds.  The  irriga- 
tion water  in  this  district  is  obtained  from  artesian  wells.  (Figs.  47 
to  50).  Artesian  water  is  usually  found  at  from  150  to  175  feet, 
and  throughout  the  whole  area  the  fldw  varies  from  a  few  feet  to  as 
much  as  40  feet  above  the  sea  level.  Around  Hastings,  where  the 
land  elevation  is  only  about  eight  feet,  many  of  the  wells  have  a 
flow  pressure  of  about  twelve  and  a  half  pounds  per  square  inch. 
A  four-inch  well  ordinarily  furnishes  sufficient  water  to  irrigate 
a  40-acre  tract,  and  a  six-inch  well  easily  cares  for  60  acres  or  more. 
Tests  made  on  the  rate  of  flow  of  a  two-inch  well  indicated  a 


SPECIAL  CULTURAL  FEATURES 


83 


capacity  of  80  gallons  per  minute.  The  water  is  more  or  less 
strongly  impregnated  with  sulfur,  giving  it  a  distinctly  hydrogen 
sulfide  smell  and  taste.  It  emerges  from  the  well  at  a  tempera- 
ture Oi  70  degrees  F.  The  irrigation  water  is  applied  to  the  grow- 
ing crops  by  means  of  open  ditches  or  dead  furrows  between  the 
raised  beds  on  which  the  crop  is  grown  (Fig.  49).  The  water 
spreads  out  over  the  somewhat  impervious  clay  sub-soil  with  which 
most  of  the  land  is  underlaid,  and  is  taken  up  by  capillary  action. 
The  crop  is  grown  on  raised  beds  of  from  8  to  16  rows  in  width. 


Fg.  49. — Irrigation  furrow  or  ditch  full  of  water. 

with  deep  dead  furrows  separating  the  beds;  the  dead  furrows 
serving  as  irrigation  channels  or  ditches  for  the  distribution  of  the 
water.  Drainage  ditches  have  to  be  provided  in  order  to  carry  oft' 
the  waste  water,  as  well  as  to  take  care  of  the  heavy  rainfalls 
Avhich  not  infrequently  occur  in  this  region  (Fig.  50).  The  drain- 
age ditch  may  be  closed  Avhile  irrigation  is  in  progress,  but  is 
opened  up  immediately  thereafter,  the  aim  being  to  remove  the 
surplus  or  waste  water  as  quickly  as  possible.  Cultivation  should 
follow  each  irrigation  in  order  to  keep  the  soil  loose  and  well 
aerated.  An  implement  known  locally  in  the  Hastings  district  as 
a  scooter  is  rather  commonly  employed  in  the  later  cultivation  to 
loosen  up  the  soil  in  the  bottom  of  the  furrow. 

In  the  Beaufort  section  of  South  Carolina,  as  well  as  in  most 


84         CULTURAL  CARE  OF  GROWING  CROP 

portions  of  Soiitlicrii  Alahiiina.  ]\Iississi|)j)i,  an<l  Louisiana.  Ww 
practice  oi"  planting  the  crop  on  well  delined  ridges  is  quite  com- 
mon. These  ridges  are  formed  hy  l)ack-t'urro\ving  the  land  and 
then  opening  up  the  ridge  with  a  middle-buster  plow;  the  seed 
pieces  l)eing  dropjjcd  in  the  furrow  thus  formed  and  covered  with 
the  middle  buster.  AVhere  high  ridging  is  practiced  (Fig.  51) 
or  where  two  rows,  spaced  about  20  inches  apart,  are  planted  on 
a  ridge,  the  distance  from  centre  to  centre  of  the  ridges  varies  from 
three  and  a  half  to  four  feet  apart  (Fig.  52).  In  lower  ridging 
the  sj)acing  is  usually  about  three  feet  ajnirt.  The  practice  of 
})lanting  two  rows  to  a  ridge  with  a  narrow  spacing  between,  has 


Fig.  50.— a  large  drainage  ditrh  luar  ^'<  r..,  I'la.  .-.how  in-  typical  vegetation  of  (he  region. 

only  been  observed  by  the  writer  in  the  Beaufort,  8.  C  section, 
and  there  on  only  a  single  farm  (Fig.  51). 

In  all  irrigated  sections  of  the  West,  outside  of  the  Stockton 
district  in  Ualiiornia  and  that  of  a  resrrictcd  area  around  Clat- 
skanie  in  Oregon;  the  usual  method  of  applying  water  to  the  crop 
is  to  run  it  down  the  furrows  between  the  rows.  Some  growers 
irrigate  in  every  furrow,  while  others  only  allow  the  M'ater  to  flow 
in  every  other  tow.  The  first  method  is  more  commonly  practised. 
Irrigation  projects  are  found  in  all  states  west  of  Minnesota, 
or  in  North  and  South  Dakota,  Nebraska,  Colorado,  Wyoming, 
Montana,  Utah,  Idaho,  Nevada,  Oregon,  Washington,  California, 
Arizona  and  New  Mexico. 

The  usual  procedure  in  irrigating  the  potato  crop  is  to  apply 
water  oiilv  when  necessary  to  keep  the  j)lants  in  an  active  stage 


THE  USUAL  PROCEDURE  IN  IRRIGATING  85 

of  growtli.  Must  growers  prefer  to  witlihold  the  first  irrigation 
until  tlie  tubers  liave  begun  to  form ;  but  this  is  not  alwa3'S  possible, 
as  there  are  seasons  in  which  the  moisture  in  the  soil  is  insufficient 
to  germinate  the  seed  pieces.  Under  such  circumstances  the  grower 
has  no  other  alternative  than  to  irrigate.  This  is  known  as 
"irrigating  up."  Other  seasons  occur  in  which,  through  lack  of 
winter  snows  or  rains  and  the  prevalence  of  drying  winds  in  the 
spring,  the  soil  moisture  is  so  deficient  that  it  becomes  necessary 


Fig.  51. — Single  row  ridging  in  the  South.     A  roller  is  often  used  to  firm  the  loose  soil 
and  increase  capillary  movement  of  moisture. 

to  irrigate  before  preparing  the  land  for  planting.  Such  practices 
are  of  course  only  possible  on  irrigation  projects  that  furnish  water 
for  early  irrigation.  Usually  3  to  4  irrigations  throughout  the 
growing  season  are  sufficient  to  make  a  good  crop.  Occasionally, 
tlie  crop  may  be  made  with  two  applications  of  water;  in  unfavor- 
able seasons,  that  is  when  there  is  practically  no  precipitation  or  an 
unusual  amount  of  windy  weather,  6  or  8  may  be  necessary. 
The  aim  of  the  irrigator  should  be  to  supply  sufficient  water  at  all 
times  to  keep  the  plant  in  a  healthy  growing  condition  throughout 
the  growing  season.     Irrigation  should  cease  from  4  to  G  weeks 


86 


CULTURAL  CARE  OF  GROWING  CROP 


before  the  harvesting  period  in  order  to  ripen  the  crop.  Some 
growers  do  not  observe  this  practice,  preferring  to  sacrifice  the 
quality  of  the  crop  for  the  sake  of  a  greater  tonnage.  The  result 
of  continuing  irrigation  almost  up  to  the  harvesting  period  is  the 
•production  of  overgrown  tubers  containing  a  high  percentage  of 
water.  Such  tubers,  on  account  of  their  unripe  condition,  are 
more  easily  injured  in  harvesting,  do  not  keep  as  well  in  storage, 
and  are  not  as  satisfactory  for  table  or  seed  j^urposes. 


^^'^^ 


Fig.  52. — Double  row  ridging  in  the  Beaufort,  S.  C,  district. 

The  Stockton  and  Clatskanie  Districts. — Inasmuch  as  the 
Stockton  and  the  Clatskanie  districts  are  practically  identical  so 
far  as  their  maiiagement  is  concerned,  the  description  of  the  methods 
pursued  in  the  former  region  may  be  regarded  as  applying  to  the 
latter  district.  As  an  aid  to  a  clearer  understanding  of  the  method 
of  applying  water  to  the  crop  in  the  Stockton  district,  it  seems 
desirable  to  give  a  brief  description  of  the  character  of  the  soil 
and  its  physiography.  This  district  embraces  what  is  known  as 
the  delta  lands  of  the  San  Joaquin  and  Sacramento  rivers,  com- 
monly referred  to  in  that  section  as  the  tule  lands,   (Fig.  53). 


THE  STOCKTON  AND  CLATSKANIE  DISTRICTS  87 


CULTURAL  CARE  OF  GROWING  CROP 


"Tule"  is  the  Mexican  name  of  a  large  bulrush  wliieh  grows 
abundantly  on  the  unreclaimed  portion  of  this  land.  The  tule 
lands  are  almost  entirely  of  organic  origin.  They  are  in  reality 
reclaimed  peat  bogs.  The  nsual  procedure  in  reclaiming  such 
land  is  to  build  a  rather  high  earthen  levee  around  a  considerable 
tract  of  land  by  means  of  a  large  dredge  (Fig.  54).  When  the 
levee  is  completed  (Fig.  55),  the  drainage  ditches  are  cut  through 


Fig 
around  a 


.  54. — The  first  step  in  the  reclamation  of  tule  land  is  that  of  constructing  a  levee 
tract  of  land.    The  soil  is  scooped  up  by  large  scoops  operated  by  a  floating  derrick. 


the  tract  and,  at  some  convenient  point,  a  large  centrifugal  pump 
is  installed  on  the  levee.  The  ojjeration  of  this  pump  by  electricity 
or  other  motive  power  soon  tends  to  lower  the  water  ta1)le  in  the 
inclosed  area.  The  water  lifted  by  the  centrifugal  pump  is  dis- 
charged, over  the  levee,  into  the  river  or  canal  ojiened  up  by  tlic 
removal  of  soil  for  the  construction  of  the  levee.  As  soon  as  the 
soil  in  the  tract  is  sufficiently  dry  to  work  it  is  plowed.  Usually, 
the  grower  plows  the  land  in  the  autumn  or  early  winter  months, 
and  fits  it  in  the  early  spring.  When  tlie  root-filled  soil  has  V)eeii 
put  in  reasonably  good  shape  it  is  ready  for  the  replowing,  necessi- 


THE  STOCKTON  AND  CLATSIvANIE  DISTRICTS 


89 


90  CULTURAL  CARE  OF  GROWING  CROP 

tated  by  practice,  in  this  section,  of  planting  the  seed  pieces  in 
every  other  furrow  as  the  land  is  being  replowed.  The  peculiar 
character  of  this  soil,  it  is  claimed,  precludes  the  use  of  the  potato 
planter.  The  real  facts  are  that,  owing  to  the  porous  character  of 
the  soil,  the  high  evaporation  of  moisture  during  the  growing  sea- 
son, and  the  high  temperature  of  the  upper  layer  of  soil  during 
the  day,  the  potato  plant  succeeds  better  when  the  seed  pieces  are 
planted  at  a  depth  of  from  6  to  8  inches.  The  present  types  of 
potato  planters  are  not  constructed  to  plant  the  seed  piece  much 
over  4  inches  in  depth.  Irrigation  is  accomplished  by  cutting  nar- 
row ditches  of  about  30  inches  in  depth  and  from  60  to  75  feet 
apart.  These  lateral  ditches  are  usually  cut  between  the  potato 
rows  after  the  plants  are  well  above  ground.  The  skill  and  pre- 
cision displayed  in  cutting  these  ditches  and  disposing  of  the  soil, 
with  but  little  disturbance  of  the  plants  in  the  adjacent  rows, 
seems  to  be  developed  to  a  high  degree  in  the  Japanese  and  Chinese 
farmers  and  laborers,  by  whom  the  larger  proportion  of  the  crop 
in  this  region  is  grown.  After  the  lateral  ditches  are  cut  and  the 
plants  are  in  need  of  moisture,  the  water  for  irrigation  purposes 
is  either  siphoned  out  of  the  river  -proper,  or  canals;  or  it  is 
admitted  through  sluice  gates  into  the  large  distributing  ditches 
which,  in  turn,  supply  the  laterals  cut  between  the  potato  rows. 
The  laterals  are  kept  full  until  the  moisture  has  transfused  through- 
out the  entire  intervening  spaces  or  strips  of  land,  after  which  it 
is  drawn  off  in  order  to  keep  the  soil  gweet.  This  process  is  repeated 
as  often  as  may  be  necessary  throughout  the  growing  season. 

QUESTIONS    ON   THE   TEXT 

1.  How   many  well   recognized   systems   of   potato   culture   are   in   vogue 

in  the  United  States?     Name  and  describe  them. 

2.  What  is  meant  by  the  term  tillage? 

3.  What  is  the  object  of  pre-germination  tillage?     What  implements  are 

used  for  it? 

4.  What  is  the  usual  level  culture  tillage  practice  after  the  plants  appear 

ahove  ground? 

5.  What  implement  does  the  southern  grower  frequently  use? 

6.  What  objection  is  there  to  the  use  of  the  one-horse  plow? 

7.  In  level  culture,  what  is  the  customary  practice  when  giving  the  crop 

its  last  cultivation? 

8.  When  should  cultivation  of  the  crop  cease? 

9.  To  what  extent   should  hand   hoeing   be  practised  in   commercial   po- 

tato production? 
10.  How  does  the  grower  avoid  hand  hoeing  in  certain  parts  of  Michigan 
and  Wisconsin? 


QUESTIONS  SUGGESTED  BY  THE  TEXT  91 

11.  What  cultural  practices  obtain   in  the  Hastings  district  in   Florida? 

12.  What  is  the  source  of  the  irrigation  water  in  this  district? 

13.  How  many  acres  will  a  four-inch  well  irrigate? 

14.  How  is  the  water  applied  to  the  growing  crop? 

15.  What  use  does  the  grower  make  of  the  implement  known  as  the  scooter? 

16.  What  special  system  of  culture  is  found  in  the  Beaufort  district  of 

South  Carolina? 

17.  How  is  water  applied  to  the  potato  crop  in  the  West? 

18.  Describe  the  practice  known  as  "irrigating  up." 

19.  How  often  should  the  crop  be  irrigated? 

20.  What  effect  has  late  irrigation  upon  the  quality  of  the  crop? 

21.  What  is  the  soil  formation  in  the  Stockton  district? 

22.  How  is  it  reclaimed? 

23.  How  is  the  crop  planted? 

24.  How  is  the  irrigation  water  applied? 

25.  By  whom  is  a  large  part  of  the  crop  grown? 

QUESTIONS  SUGGESTED  BY  THE  TEXT 

1.  Describe  the  most  common  local  systems  of  culture. 

2.  What  implements  are  common  in  this  work? 

3.  How  much  pre-germination  tillage  is  practised  by  your  local  growers? 

4.  Is  irrigation  in  any  form  used  by  your  growers?     Describe  it. 


CHAPTER  TX 
POTATO  PRODUCTION  IN  THE  SOUTH 

In  many  respects  the  production  of  potatoes  in  the  South  is 
quite  distinct  from  that  of  the  North  and  West.  The  chief  points 
of  difference  are  first,  that  the  potato  is  very  largely  gro\\Ti  in  the 
South  as  an  early  or  truck  crop ;  second,  that  there  are  three  rather 
distinct  crop  periods,  viz. :  the  early  or  truck  crop,  the  late  or  main 
crop,  and  the  fall  crop.  A  full  discussion  of  these  three  crops  is 
presented  in  a  later  portion  of  this  chapter. 

Extent  and  Importance  of  the  Crop. — The  usual  procedure 
in  judging  the  importance  of  any  crop  is  by  comparing  production 
in  any  given  locality  or  region  with  that  of  other  sections.  For- 
tunately such  a  comparison  is  made  possible  through  the  geographi- 
cal division  of  the  United  States,  by  the  Bureau  of  Crop  Estimates, 
into  three  great  regions,  known  as  the  "northern,"  "far  west,"  and 
"southern."  The  states  embraced  in  each  of  these  areas  are  given 
in  next  table.  This  shows  that  the  northern  division  includes 
21  states,  far  west  11,  and  the  southern  16. 

Distribution  by  Sections. — The  December  1st  report  of  tlie 
Bureau  of  Crop  Estimates  shows  a  total  production,  in  tlie 
United  States,  of  428,368,000  bushels  of  potatoes.  Of  this  amount 
the  21  northern  states  produced  304,523,000  bushels,  the  11  far 
western;  states  59,275,000  bushels,  and  the  16  southern  states 
64,570,000  bushels.  Expressed  in  percentages,  the  northern  group 
of  states  produced  71.09  per  cent;  the  far-western  13.84  per  cent; 
and  the  southern  group  15.08  per  cent.  It  is  thus  seen  that  the 
southern  potato  crop  represents  but  a  little  over  one-seventh  of 
the  entire  crop  of  the  United  States. 

The  Money  Value. — If,  however,  we  consider  the  crop  from 
the  stand})oint  of  its  money  value  to  the  producer,  which,  after  all, 
is  the  only  proper  basis  of  comparison,  it  assumes  an  entirely 
different  degree  of  importance,  because  the  early  truck  crop  of 
the  South  usually  sells  for  a  much  higher  price  than  that  of  the 
late  crop  in  the  North.  This  is  due  to  the  fact  that  the  northern 
or  western  consumer  is  willing  to  pay  a  considerable  premium  for 
new  potatoes  over  that  for  old  stock.  Hence,  it  can  be  readily  seen 
92 


RELATIVE  IMPORTANCE  OF  THE  THREE  CROPS 


93 


that  the  new  potato  crop  from  the  South  has  a  financial  value 
out  of  all  proportion  to  its  volume.  There  are  seasons,  of  course, 
in  which  the  May  to  August  prices  for  southern  stock  rule  low. 
This  is,  as  a  rule,  due  to  either  one  of  two  conditions,  viz.,  a  large 
holdover  stock  of  the  northern  crop,  or  excessive  production  in 
the  South,  which  tends  to  depress  the  market  for  both  the  old  as. 
well  as  the  new  stock.  Such  a  condition  occurred  during  the 
Spring  of  1918,  when  the  growers  in  northern  Florida  were  obliged 
to  dispose  of  a  considerable  portion  of  their  crop  at  an  actual 
loss.  For  this  reason,  the  production  of  early  potatoes  in  the 
South  is   a  somewhat   uncertain   proposition,   because   the  grower 


List  of  States  Included  in  the  Three  Geographical  Areas 


Northern 

Far  western 

Southern 

.Maine 

Illinois 

Montana 

Delaware 

Georgia 

^'evv  Hampshire 

^lichiiian 

Wyoming 

Maryland 

Florida 

\  erinont 

Wisconsin 

Colorado 

V^irginia 

Alabama 

]Massacliusetts 

Minnesota 

New  Mexico 

West  Virginia 

Mississippi 

^\hode  Island 

Iowa 

Arizona 

North    Carolina 

Louisiana 

Connecticut 

Missouri 

Utah 

South  Carolina 

Texas 

New   York 

North  Dakota 

Nevada 

Tennessee 

Oklahoma 

New  Jersey 

South  Dakota 

Idaho 

Kentucky 

Arkansas 

Pennsylvania 

Nebraska 

Washington 

Ohio 

Kansas 

Oregon 

Indiana 

California 

has  com])aratively  little  leeway  in  tlio  marketing  of  his  crop.  If 
the  crop  is  a  normal  one,  he  must  market  it  within  a  relatively 
short  time  or  else  he  will  be  in  competition  with  growers  farther 
]]orth;  then  too,  it  must  be  harvested  before  a  certain  period,  else 
crops  that  are  to  succeed  it  will  suffer  as  a  result  of  not  having 
entire  use  of  the  land.  There  is  yet  another  reason  why  the 
harvesting  of  the  southern  crop  cannot  be  very  greatly  delayed ; 
that  is,  that  it  is  not,  as  a  rule,  safe  to  allow  the  crop  to  remain  in 
the  ground  for  any  considerable  period  after  it  is  ripe,  owing  to 
danger  from  tuber  decay.  This  applies  more  particularly  to  the 
southern    tier   of   states. 

Relative  Importance  of  the  Three  Crops. — A  fairly  good 
idea  of  the  relative  importance  of  the  early  crop  to  that  of  the 
late  or  main  crop,  and  the  fall  crop  which  are  here  considered 
together,  may  be  obtained  from  a  study  of  the  data,  published  by  the 


94  POTATO  PRODUCTION  IN  THE  SOUTH 

Bureau  of  Crop  Estimates,  in  the  monthly  report  for  May,  1918, 
in  which  the  disposal  of  the  crop  is  given  by  months  for  each  of 
the  16  states.  These  data  which  are  assembled  in  the  next  table, 
afford  a  very  good  index  to  the  relative  importance  of  the  early 
crop  in  each  of  tlie  States.  It  is  admitted  that  these  figures 
are  approximate,  rather  than  actual;  the  disposal  of  an  early  crop 


FlOtUa.  ^     I 
LouAs\a.na.     I 

"7"    . 

OkUKomi     I 
Greet:  Qva        I 

A    kP"     "/'     I 


hsi. 


FiQ.  56. — Approximate  percent  marketed  as  an  early  crop,  1918. 

may  be  hastened  or  delayed  according  to  whether  the  supply  is 
short  or  ample,  or  the  market  active  or  sluggish.  It  is  believed, 
however,  that  these  data  are  of  value  in  that  they  afford  a  very 
fair  index  of  the  volume  of  the  early  crop,  and  the  period  of  time 
during  which  it  is  normally  marketed  in  each  state.  The  per  cent 
given  represents  that  portion  of  the  crop  harvested  and  marketed, 
during  the  periods  mentioned.  It  is  conceivable  that  some  may 
disagree  with  the  arbitrary  time  division  that,  of  necessity,  had  to 


THE  FLUCTUATION  IN  TOTAL  PRODUCTION 


95 


be  made  in  the  preparation  of  tiiese  data,  but  it  is  believed  that 
they  are  approximately  correct : 

Owing  to  the  fact  that  there  are  no  data  bearing  upon  the 
extent  of  the  late  or  main  crop,  and  the  fall  crop  production  in 
the  South,  the  only  possible  separation  of  the  crops  on  the  produc- 
tion basis  is  that  of  comparing  the  early  with  that  of  the  other 
two  crops. 

The  significance  of  the  data  presented  in  the  foregoing  table 
may  be  more  readily  grasped  by  a  study  of  figure  56  in  which 


Approximate  per  cent  Marketed  as  an  Early  Crop 
from  Late  Crop. 


Distinguished 


State 

Date  Marketed 

Per  cent 

State 

Date  Marketed 

Per  cent 

Alabama  .  . . 

Apr.  to  Aug.  31 

86 

Mississippi . . 

Apr.  to  Aug.  31 

85 

Arkansas  . . . 

May  to    "      " 

53 

North  Car. .  . 

Mayto   "     " 

48 

Delaware .  . . 

June  to     "      " 

31 

Oklahoma  . . 

Mayto   "     " 

71 

Florida 

Feb.  to    "      " 

93 

South  Car. .  . 

Apr.  to   "     " 

86 

Georgia  .... 

May  to    "      " 

63 

Tennessee  .  . 

Mayto   "     " 

35 

Kentucky  . . 

June  to    "      " 

20 

Texas 

Apr.  to   "     " 

78 

Louisiana . . . 

Apr.  to    "      " 

91 

Virginia  .... 

Mayto   "     " 

43 

Marj'land  .  . 

June  to    "      " 

27 

West  Virginia 

June to   "     " 

19 

these  data  are  graphically  presented  or  visualized.  It  is  appar- 
ent from  this  graph  that  the  early  crop  is  of  less  relative  impor- 
tance to  the  other  two  crops  in  the  northern  tier  of  the  southern 
group  of  states  than  in  the  strictly  southern  ones. 

The  fluctuation  in  total  production  of  the  sixteen  states 
and  the  farm  value  of  the  crops  during  the  five-year  period  1914- 
1918  inclusive,  as  shown  in  figure  57,  is  especially  interesting  in  that 
it  covers  the  period  in  which  the  late  World  War  occurred.  These 
data  are  indicative  of  the  expansive  flexibility  of  the  potato  indus- 
try in  the  South  whenever  the  necessity  for  more  food  arises, 
or  whenever  a  partial  crop  failure  in  the  North  assures  a  good 
market  for  the  early  crop. 

A.  THE  EARLY  OR  TRUCK  CROP 

As  has  been  previously  shown,  the  early  crop  of  potatoes  in  the 
South  is  by  far  the  most  important  part  of  the  Irish  potato  indus- 
try of  thai:  region.     It  is  grown,  as  a  rule,  in  what  might  be 


96  POTATO  PRODUCTION  IN  THE  SOUTH 

designated  as  intensive  potato-producing  centres.  These  centres 
of  production  usually  owe  their  origin  to  certain  favorable  condi- 
tions for  growing  and  ship])ijig  early  potatoes.  Concentration  of 
the  industry  also  affords  other  benefits  to  the  growers  in  that  it 
brings  the  buyers  to  their  doors.  This  insures  competitive  buying 
and,  in  consequence,  a  better  price  to  the  grower.  Active  buying 
is  of  greater  importance  to  the  southern  grower  than  to  the  north- 
ern one,  because  he  is  obliged  to  market  his  early  crop   within 


/L  '  '  '  '  ' 

TUilh'oiis  mVu5V\fe\s  a.Yiddo\ia.rs. 
■■Bu-shtls 

Fig.  57. — Average  annual  production  in  bushels  and  value  of  same  for  the  sixteen 
southern  states  during  the  years  1914  to  1918. 

a  comparatively  short  time  after  it  reaches  marketable  size.  It 
is  not  feasible  to  store  it,  as  is  the  case  with  the  northern  crop. 
In  addition  to  this,  the  southern  crop  must  be  dug  in  order  to 
make  the  land  availahle  for  the  ensuing  crops,  such  as  corn,  cow- 
peas,  etc.  The  conditions  that  are  generally  regarded  as  favorable 
■for  the  production  of  an  early  crop  are :  ( 1 )  a  light  sandy  loam 
soil,  possessing  good  drainage  and  not  subject  to  drought;  (2)  good 
shipping  facilities,  either  by  rail  or  boat;  (3)  plenty  of  farm  labor; 
(4)  a  short  haul  to  shipping  point. 

Commercial  Production  Centres. — There  are  a  numl)er  of 
well  develo])ed  commercial  ])otato-production  centres  in  the  South. 
The  more  widely  known  centres  or  districts  are  Hastings,  Fla. ; 
Beaufort  and  Charleston,  S.  C. ;  Beaufort,  N.  C;  Norfolk  and  the 


VARIETIES  GROWN  97 

Eastern  Shore,  Va.;  the  southern  i^ortion  of  the  Maryhmd  penin- 
sula; Louisville,  Ky.;  Columbia,  Tenn.;  Fort  Smith,  Ark.;  Fort 
Gibson,  Okla.;  Eagle  River,  Wharton  and  Brownsville,  Tex.,  and 
Alexandria,  and  Bayou  La  Fourche,  La.  These  localities  have 
developed  into  relatively  large  producing  centres  because  the  neces- 
sary elements  of  success  were  present.  The  only  exception  that 
might  be  taken  to  the  preceding  statement  is  with  respect  to  the 
Brownsville  district,  which  has  only  come  into  prominence  within 
the  past  year  or  two.  A  few  of  the  many  elements  essential  to 
the  development  of  any  large  industry,  and  particularly  of  a  rela- 
tively bulky  commodity  are  good  shipping  facilities  and  a  favor- 
able soil  and  climate.  Then,  too,  the  larger  the  production  in 
any  given  locality  the  more  likely  it  is  to  attract  a  greater  number 
of  buj^ers.  In  addition  to  this,  is  the  application  of  good  business 
methods  in  the  growing  and  marketing  of  the  crop.  Finally,  the 
growers  themselves  are  largely  responsible  for  the  success  or  failure 
of  potato-production  centers.  Many  new  localities  engage  in  potato 
})roduction  in  a  more  or  less  extensive  manner  each  year;  but 
few  of  them  persist  for  any  length  of  time,  for  the  simple  reason 
that  some  conditions  are  not  conducive  to  the  development  of 
a  successful  industry. 

•Soils. — If  one  were  to  study  the  soil  types  in  each  of  the 
production  areas  mentioned,  they  would  be  found  to  be  of  a 
more  or  less  similar  character  in  that  most  of  them  are  of  a  warm 
sandy  nature.  Those  in  the  Atlantic  Coastal  Plain  area  consist 
very  largely  of  the  Norfolk  sandy  loam  series.  In  the  Hastings 
district  in  Florida,  the  best  potato  soil  is  known  as  the  Bladen  fine 
sand  or  sandy  loam  series.  The  Eagle  Lake  and  Wharton  soil 
types  are  of  a  distinctly  sandy  nature,  and  are  for  the  most  part 
of  alluvial  origin.  Those  of  the  Fort  Gibson  and  Fort  Smitli 
sections  are  largely  river  bottom  soils  of  the  Grand  and  Arkansas 
Rivers,  consisting  of  a  sandy  loam  sometimes  bordering  on  a 
heavy  loam  soil.  Those  of  Alexandria,  in  Louisiana,  and  Louis- 
ville, in  Kentucky,  are  also  of  a  sandy  character  and  easily  han- 
dled. They  are  soils  that  warm  up  quickly  in  the  late  winter  or 
early  spring,  that  respond  generously  to  liberal  fertilization  and 
good  cultural  treatment;  and  are  well  adapted  to  the  production 
of  early  crops. 

Varieties   Grown. — The  varieties  of  potatoes  grown  for  the 
early  crop  in  the  South  are  the  Irish  Cobbler  (Figs.  337,  238). 
7 


98  POTATO  PRODUCTION  IN  THE  SOUTH 

Triumph  (Figs.  239,  240),  and  Spaulding  No.  4  (Rose  No.  4) 
(Fig.  246).  The  Irish  Cobbler  is  most  extensively  grown  in  the 
Atlantic  Coast  States  from  Georgia  to  Delaware,  and  the  Louis- 
ville district,  in  Kentucky.  It  is  also  grown  to  some  extent  in 
most  of  the  other  states.  The  Triumph  is  grown  most  extensively 
in  southern  Florida,  Alabama,  Mississij^pi,  Louisiana,  Texas, 
Oklahoma,  Arkansas  and  Tennessee.  Spaulding  No.  4  is  almost 
entirely  restricted  to  the  north  central  and  northeastern  portion 
of  Florida.  It  is  grown  practically  to  the  exclusion  of  all  other 
varieties  in  the  Hastings  district. 

Source  of  Seed  Supply. — Outside  of  the  relatively  small 
amount  of  second  crop  seed  produced  in  certain  localities  in  the 
South,  the  southern  grower  is  wholly  dependent  upon  northern 
grown  seed  stock  for  the  planting  of  his  early  crop.  The  potato 
growers  of  northern  Maine  furnish  a  large  portion  of  the  Irish 
Cobbler  and  Spaulding  No.  4  seed  stock  and  lesser  amounts  of 
the  Triumph.  Wisconsin,  Minnesota  and  Nebraska  supply  a 
large  share  of  the  Triumph  seed  used  in  the  Triumph-producing 
areas  of  the  South.  Usually  the  grower  purchases  his  seed  from 
his  local  commission  man  or  seed  dealer.  In  the  extreme  South, 
delivery  of  northern  grown  stock  must  be  made  during  December 
and  January,  thus  necessitating  its  shipment  shortly  after  it  is 
harvested.  In  the  Norfolk  and  Eastern  Shore  of  Virginia  and 
Maryland  district,  deliveries  are  made  during  the  latter  part  of 
Januar}^  and  extending  into  March.  The  seed  stock  for  this  area 
is,  therefore,  purchased  in  the  North,  with  the  understanding  that 
it  must  be  held  there  until  the  time  mentioned.  This  necessitates 
its  shipment  at  a  period  of  the  year  when  extreme  cold  w^eather  is 
quite  apt  to  prevail,  thus  running  the  risk  of  having  it  frozen  or 
overheated  during  transit.  The  overheating  of  seed  enroute  is 
likely  to  occur  when  heavy  firing  is  necessary  to  prevent  frost 
getting  into  the  car.  It  has  always  seemed  to  the  writer  that  in 
order  to  avoid  these  risks,  as  well  as  that  of  delays  in  delivery  due 
to  weather  exigencies  and  car  shortage,  the  southern  grower  could 
well  afford  to  provide  suitable  storage  houses  or  warehouses  for  the 
holding  of  the  seed  throughout  the  late  autumn  and  early  winter 
months.  If  such  provision  were  made,  the  southern  grower  could 
purchase  his  seed  stock  subject  to  fall  delivery,  and  thereby  secure 
it  at  a  much  more  favorable  price  than  that  demanded  for  winter 
delivery.     It  is  further  believed  that  the  Southern  grower  could 


DATE  OF  PLANTING 


99 


effect  a  very  considerable  saving  in  the  purchase  of  his  seed  stock  by 
the  growers  organizing  in  his  section  into  a  cooperative  purchas- 
ing association,  and  sending  one  or  more  representative  growers  to 
the  seed  producing  centres  during  the  growing  season,  with  instruc- 
tions to  arrange  for  the  purchase  of  the  required  amount  of  seed 
from  the  healthiest  and  best  looking  fields.  This  would  guarantee 
them  high  quality  seed  and  at  the  same  time  assure  an  early  and 
prompt  delivery  in  the  fall.  At  the  present  time,  the  difference  in 
cost  per  sack  between  autumn  and  -winter  delivery  averages  about 
$1.00.  A  wider  margin  of  difference  than  this  obtains  when  ship- 
ments are  made  subject  to  the  grower's  or  dealer's  risk. 

Approximate  Dates  of  Planting  Early,  Lale  or  Main,  Second,  and  Fall 
Crop  Potatoes  in  the  South* 


State 

Date  of  planting 
early  erop 

Date  of  planting  late 
or  main  orop 

Date  of  planting 
second  and  fall  crop 

Alabama 

Jan.  15  to  Feb.  15 
Feb.  15  to  Mar.  15 
Mar.  20  to  April  20 
Nov.  20  to  Mar.  1 
Jan.  15  to  Feb.  15 
Mar.  1  to  April  10 
Jan.  15  to  March  10 
Mar.  1  to  April  25 
Jan.  15  to  Feb.  25 
Feb.  15  to  Mar.  25 
Feb.  15  to  Mar.  20 
Feb.  1  to  Mar.  15 
Mar.  1  to  April  10 
Jan.  1  to  Mar.  15 
Feb.  15  to  April  1 
Mar.  15  to  April  .30 

April  25  to  May  25 

April  25  to  May  25 
April  15  to  May  20 

April  25  to  June  5 

April  25  to  May  30 

April  20  to  May  25 
April  15  to  May  20 
April  1  to  May  15 
April  20  to  May  25 
April  25  to  May  20 

Aug.  15  to  Sep.  15 

July  15  to  Aug.  15 

Aug.  1  to  Sep.  1 
July  1  to  July  25 
Aug.  15  to  Sep.  1 
June  20  to  July  20 
Aug.  15  to  Sep.  1 
July  10  to  Aug.  10 
June  15  to  July  10 
July  15  to  Aug.  20 
July  10  to  Aug.  1 
July  1  to  Sep.  1 
July  1  to  Aug.  10 
June  25  to  July  10 

North  Carolina 

Oklahoma 

South  Carolina 

Texas 

West  Virginia 

*  These  data  are  based,  in  part,  upon  information  obtained  from  the  U.  S.  Bureau 
of  Crop  Estimates,  and  partly  from  the  writer's  personal  observation  or 
knowledge  of  dates  of  planting  in  many  of  the  states. 

Date  of  Planting. — The  dates  of  planting  in  the  table  are 
intended  to  represent  the  approximate  period  in  which  the  early, 
late,  and  fall  crops  are  planted.  The  data  for  the  late  and  fall 
crops  being  presented  in  connection  with  that  of  the  early  in 
order  that  the  three  sets  of  dates  could  be  easily  compared.  In 
all  instances  the  earliest  date  for  the  early  crops  and  the  latest 
date  for  the  fall  crop  refers  to  the  southern  or  warmer  portion  of 
the  state,  while  the  reverse  dates  apply  to  the  northern  portion 


100  POTATO  PRODUCTION  IN  THE  SOUTH 

of  it.  For  example,  tlie  date  of  planting  the  early  crop  in  Texas 
varies  from  January  1st  to  March  15th;  while  the  fall  crop  i)lant- 
ing  extends  from  July  1st  to  September  1st. 

It  should  be  borne  in  mind  that  the  dates  given  are  not  intended 
to  be  taken  too  literally.  They  simply  represent,  as  stated,  the 
approximate  range  of  time  in  which  the  bulk  of  the  planting  of 
each  crop  occurs.  It  is  quite  possible  that  some  particularly  well 
favored  locality  could  plant  earlier  than  the  earliest  date  given, 
while  in  other  cases  later  planting  than  the  last  date  given  might 
be  necessary. 

Early  Marketing. — In  the  production  of  early  potatoes  in  the 
South  the  object  of  the  grower  is  to  bring  his  crop  to  marketable 
maturity  as  quickly  as  possible.  To  do  this,  it  is  necessary  to 
plant  the  seed  as  early  as  the  soil  and  the  climatic  conditions  will 
l)ermit.  On  certain  farms,  or  in  some  limited  areas  as,  for  exam- 
])le.  Federal  Point  in  the  Hastings  district,  Florida,  tlie  crop  may 
be  planted  from  one  to  tw^o  wrecks  earlier  than  the  rest  of  the  sec- 
tion. At  Federal  Point  planting  very  often  begins  in  the  latter 
part  of  December,  wdiereas  in  the  district  as  a  whole,  it  is  usually 
not  well  under  way  until  the  middle  of  January.  As  might  be 
expected  the  crop  is  frequently  injured  by  late  spring  frosts. 
Occasionally  the  frost  injury  to  the  plants  is  severe  enough  to  cause 
a  material  reduction  in  yield;  and  on  rather  rare  occasions  it  may 
actually  kill  the  plants.  Light  frosts  simply  retard  the  maturity 
the  North. 

B.    LATE    OR    ]MAIX    CROP    POTATOES 

Generally  speaking,  late  or  main  crop  potato  production  in  the 
South  is  confined  to  those  regions  or  localities  in  wdiich  it  is  not 
])ossible  to  produce  an  early  crop.  For  example,  in  Maryland, 
Virginia,  West  Virginia,  North  and  South  Carolina,  Georgia, 
Tennessee,  and  Kentucky,  late  potatoes  are  grown  in  the  mountain- 
ous sections  wdiere  the  climatic  conditions  approach  those  in 
the  north. 

Late  or  Main  Crop  Potatoes  Defined. — In  order  to  avoid 
the  possibility  of  confusion  in  the  mind  of  anyone  concerning  what 
is  meant  by  late  or  main  crop  potatoes,  the  following  ex]ilanation 
is  offered.  Late  or  main  crop  varieties  are  those  that  require  a 
longer  season  in  which  to  reach  maturity;  in  other  words  they  are 
late  maturing  varieties  and  as  such  are  unsuited  for  early  crop 


FALL  CROP  POTATOES  101 

production.  They  are  normally  planted  after  all  danger  from 
late  spring  frosts  has  passed.  The  crop  is  planted,  cared  for,  and 
liarvested  in  practically  the  same  manner  as  that  in  the  North, 
and  like  the  northern  crop  is  intended  for  fall  and  win- 
ter consumption. 

Soil. — A  greater  variety  of  soil  may  be  used  in  the  growing 
of  late  crop  potatoes  because  the  element  of  earliness  is  not  an 
important  consideration ;  hence  heavier  and  naturally  colder  soils 
are  more  satisfactory  than  the  lighter  and  warmer  ones  provided 
they  are  well  drained. 

Varieties  Grown. — The  varieties  most  commonly  grown  for 
the  late  crop  are  those  belonging  to  the  Green  Mountain  and 
Rural  groups  of  potatoes,  such  as  the  Green  Mountain,  (Fig.  359, 
Chap.  23).  Gold  Coin,  Delaware  and  Snow,  in  the  first  group 
and  the  Rural  New  Yorker  No.  3,  (Fig.  3fil,  Chap.  23).  Carman 
No.  3,  Sir  Walter  Raleigh  and  Russet  Rural  in  the  second  group. 
Other  varieties  such  as  the  Peerless,  Mammoth  White  Pearl,  White 
Star  are  grown  to  a  much  lesser  extent.  The  Early  Rose  and 
Early  Ohio  are  grown  to  some  extent  for  late  crop  use. 

Importance  of  the  Crop. — As  no  attempt  has  ever  been  made 
by  the  Bureau  of  Crop  Estimates,  the  U,  S.  Census,  or  any  other 
agency  to  distinguish  between  the  late  crop  and  the  fall  crop 
there  is  no  way  of  determining  what  proportion  of  the  total  pro- 
duction of  these  two  crops  is  represented  by  the  late  crop.  It 
is  safe  to  say,  however,  that  in  the  states  specifically  mentioned 
the  ])roportion  is  strongly  in  favor  of  the  late  crop. 

C.    FALL    CROP    POTATOES 

The  chief  points  of  difference  between  the  late  or  main  crop 
and  the  fall  crop  of  potatoes  is  that  the  latter  is  planted  in  mid- 
summer or  later  and  is  intended  to  mature  during  the  late  fall 
months.  Fall  crop  potatoes  really  consist  of  two  rather  distinct 
crops,  viz. :  the  fall  crop  proper  and  second  crop  potatoes.  The 
first  crop  consists  of  later  maturing  varieties  intended  for  winter 
consumption ;  while  the  second  crop  consists  of  early  varieties 
planted,  as  a  rule,  after  the  first  crop  is  harvested.  The  crop  pro- 
duced from  this  second  planting  is  generally  used  as  seed  stock  for 
the  early  crop  of  the  ensuing  year;  in  fact  it  might  be  stated  that, 
when  grown  on  a  commercial  basis,  the  production  of  second  crop 
seed  is  usually  the  sole  motive  of  the  grower. 


102  POTATO  PRODUCTION  IN  THE  SOUTH 

Fall  Crop  Proper. — Fall  crop  potatoes  are  usually  only  grown 
in  those  sections  of  the  South  in  which  the  growing  season  is 
long  enough  to  produce  two  crops.  Or,  to  state  the  proposition 
another  way — where  early  crop  potatoes  are  produced.  Exceptions 
to  this  statement  may  be  cited  as,  for  example,  certain  portions 
of  Virginia,  Maryland,  and  District  of  Columbia,  which  are  in 
no  sense  early  or  truck  crop  potato  sections. 

Fall  Varieties  Grown. — The  variety  that  is  almost  univer- 
sally grown  as  a  fall  crop  potato  is  variously  known  under  the 
names  of  McCormick  (Fig.  266),  German  Peachblow,  Lookout 
Mountain,  Hoosier,  and  Blush  depending  upon  the  locality  of  the 
South  in  which  it  is  grown.  It  is  a  strong-growing,  late-maturing 
variety  which  possesses  an  unusual  degree  of  heat  and  drought 
resistance  which  enables  it  to  thrive  under  climatic  conditions 
that  are  oftentimes  quite  injurious  to  the  other  varieties.  Owing 
to  these  qualities  it  is  the  surest  cropper  of  any  fall  variety  now 
known  in  the  South.  A  sport  of  this  variety  known  as  the  White 
McCormick  has  found  much,  favor  with  Maryland  growers,  and 
its  popularity  seems  to  be  spreading  to  other  southern  states. 
As  its  name  implies  it  is  a  white-skinned  potato,  with  fewer  and 
shallower  eyes  than  the  true  McCormick  which  has  numerous  and 
rather  deep  eyes.  It  is  also  of  better  table  quality,  and  seems  to  be 
fully  as  resistant  to  heat  and  drought  as  the  true   McCormick. 

Other  varieties  that  may  be  grown  for  a  fall  crop  are  the 
same  as  those  mentioned  for  the  late  crop,  viz.,  the  various  va- 
rieties belonging  to  the  Green  Mountain  and  the  Rural  groups, 
the  Peerless,  White  Star,  Burbank,  and  in  some  few  localities  the 
Early  Rose  and  the  Early  Ohio. 

The  McCormick  and  White  McCormick  varieties  possess  other 
characteristics  than  those  of  resistance  to  heat  and  drought  and 
sure  croppers,  which  make  them  still  more  desirable  to  the  south- 
ern grower.  These  characteristics  are  their  long-keeping  quali- 
ties and  their  slowness  to  germinate  or  sprout  in  the  spring.  Many 
growers  are  able  to  keep  them  from  germinating  seriously  until 
planting  time  the  ensuing  summer,  without  resorting  to  putting 
them  in  cold  storage.  As  few  of  the  growers  are  provided  with 
good  storage  it  is  readily  seen  that  this  is  a  very  desirable  quality. 
When  the  other  varieties  are  used,  the  grower  is  obliged  to  procure 
northern  grown  seed  of  the  preceding  season's  crop  and  hold  it 
over  in  some  suitable  storage  house,  until  shortly  before  planting 


SECOND  CROP  CULTURAL  PRACTICES  103 

time  when  it  is  required  for  use.  This,  necessarily,  increases  the 
cost  of  the  seed  to  the  grower. 

Second  Crop  Potatoes. — Under  this  division  of  potato  pro- 
duction is  included  all  early  varieties  that  are  primarily  grown  as 
a  second  crop,  or  late  crop,  for  the  production  of  seed  potatoes 
intended  for  use  in  the  planting  of  the  ensuing  year's  early  or 
truck  crop. 

Strictly  speaking,  the  only  genuine  second  crop  potatoes  grown 
in  the  United  States  are  those  produced  in  regions  where  the 
Triumph  is  the  leading  early  variety;  as,  for  example,  in  the 
Fort  Smith  and  Fort  Gibson  districts  in  Arkansas  and  Oklahoma, 
where  the  tubers  from  the  early  crop  are  used  for  planting  the 
second  crop.  This,  in  the  writer's  Judgment,  is  true  second  crop 
potato  production. 

In  the  Louisville,  Kentucky,  and  the  Norfolk  and  Eastern 
Shore  of  Virginia  and  Maryland  districts,  as  well  as  certain  sections 
of  North  and  South  Carolina  where  the  Irish  Cobbler  is  g^o^vn 
as  an  early  crop,  it  is  not  possible  to  use  seed  from  this  crop  for 
the  planting  of  the  second  crop,  because  the  period  between  the 
harvesting  of  the  first  crop  and  the  planting  of  the  second  crop 
is  not  sufficiently  long,  and  what  is  still  more  important,  the  Irish 
Cobbler  variety  apparently  requires  a  longer  rest  period  than 
the  Triumph.  The  seed  used  has  to  be  imported  from  the  North, 
and  consists  of  the  preceding  year's  late  or  main  crop,  which  has 
been  held  over  in  cold  storage  during  the  warm  weather  of  late 
spring  and  early  summer.  In  the  Louisville  district  second  crop 
seed  is  held  over  in  cold  storage. 

The  second  crop,  whether  in  the  Fort  Smith  or  the  Louisville 
districts,  is  usually  grown  on  land  that  has  produced  an  early  crop ; 
it  is  generally  planted  in  the  same  rows  without  the  application 
of  any  additional  fertilizer. 

Second  Crop  Cultural  Practices. — In  view  of  the  varied 
methods  in  vogue  in  the  handling  of  the  tubers  from  the  first 
crop,  during  the  interim  between  harvesting  the  one  and  planting 
the  other,  it  seems  desirable  to  briefly  consider  the  six  plans.  For 
the  sake  of  convenience,  these  practices  are  numbered. 

Practice  No.  1. — The  small  or  unsalable  potatoes,  really  the 
culls,  and  the  few  marketal^le  tubers  overlooked  by  the  pickers, 
are  thrown  back  into  the  furrow  opened  up  by  the  plow  in  turn- 
ing out  the  first  crop,  or  in  the  freshly  opened  furrow  if  the  ele- 


104  POTATO  PRODUCTION  IN  THE  SOUTH 

vator  digger  is  used.  The  aim  of  the  grower  is  to  grow  the  second 
crop  in  the  same  drill  row  as  the  first  one.  This  method  is 
followed  in  order  to  give  the  second  crop  plants  the  opportunity 
of  using  up  whatever  residual  plant  food  there  may  be  left  in 
the  soil  from  the  first  application  of  commercial  fertilizers.  Some- 
times the  newly  harvested  tubers  are  planted  in  some  previously 
l)repared  land  on  which  potatoes  had  not  been  grown  during  that 
current  season.  The  practice  of  planting  back  in  the  same  fur- 
rows as  soon  as  the  first  crop  is  removed  has  the  advantage  of 
minimizing  labor;  but  the  disadvantages  of  a  slow  and  imperfect 
germination,  and  the  inevitable  weed  growth  that  is  sure  to  take 
possession  of  the  soil  before  the  seed  germinates,  are  factors  that 
need  to  be  carefully  considered. 

Practice  No.  2. — This  practice  differs  from  the  foregoing  in 
that,  instead  of  planting  the  culls  where  they  are  to  grow  imme- 
diately after  harvesting  them,  they  are  stored  in  trenches  to  a 
depth  of  from  -i  to  6  inches  and  covered  ^\dth  a  heavy  layer  of 
soil.  The  trench  should  be  located  on  well  drained  land.  It 
may  be  opened  with  a  plow,  and,  after  the  trench  is  filled  witli 
])otatoes,  the  same  implement  may  be  used  in  covering  the  seed. 
They  are  left  in  this  condition  until  wanted  for  planting,  which 
would  be  approximately  from  three  to  five  weeks;  then  the  trench 
is  opened  and  the  potatoes  sorted  over.  Only  those  which  are 
showing  sprouts  are  selected  for  seed  purposes,  thus  insuring  a 
quick  germination  and  a  good  stand  of  plants.  The  disadvantage 
of  this  practice  is  that,  when  sufficiently  heavy  rains  occur  to 
soak  the  soil  surrounding  the  potatoes  and  this  is  followed  by 
hot  weather,  heavy  losses  from  tuber  decay  may  occur.  This  con- 
dition could  be  obviated  by  covering  the  trench  so  as  to  shed 
water,  or  by  burying  the  potatoes  on  raised  beds,  which  could 
be  covered  if  necessary.  Nothing  but  sound  stock  should  be 
handled  in  this  manner. 

Practice  No.  S. — This  method  differs  from  1  and  3  in  that  the 
tubers  are  spread  out  on  the  ground  in  some  shaded  place,  as 
under  a  building,  in  a  shed,  or  under  a  tree,  and  allowed  to  turn 
green  for  from  three  to  six  weeks  before  planting.  This  allows 
the  grower  as  in  2  to  select  for  seed  purposes  only  those  tubers 
Avhich  show  signs  of  sprouting. 

Practice  No.  Jf. — This  method  usually  differs  from  No.  3  in 
but  one  detail,  which  is  that  the  tubers  are  covered  with  a  layer 


SECOND  CROP  CULTURAL  PRACTICES  105 

of  straw,  hay,  or  other  coarse  material,  which  partially  protects 
them  from  the  light  and,  to  some  extent,  governs  loss  of  moisture. 
Some  growers  go  a  step  farther  in  this  method  by  occasionally 
moistening  the  straw  covering. 

Practice  No.  5. — This  practice  is,  so  far  as  known,  a  com- 
paratively new  one.  It  consists  in  immediately  placing  the  seed 
potatoes  from  the  first  crop  in  cold  storage,  where  they  are  held  at 
a  temperature  of  33  degrees  P.  from  four  to  five  weeks,  after 
which  they  are  taken  out  and  allowed  to  warm  up  for  a  few  days 
liefore  planting.  The  effect  of  low  tenijierature  on  the  new  potato 
is  to  shorten  the  rest  period  and  thus  hasten  germination. 

Practice  No.  G. — This  method  is  one  which  may  be  practiced 
in  connection  with  any  of  the  preceding  ones.  It  consists  iu  clip- 
ping off  the  seed  ends  or  portions  of  the  skin  of  small  tubers 
intended  for  planting  whole.  By  this  practice,  it  is  claimed, 
earlier  and  better  germiiiation  can  be  secured  than  where  the 
surface  of  the  tuber  is  not  mutilated.  Where  the  seed  potato  is 
cut,  the  same  result  is  secured.  The  actual  effect  of  removal 
of  the  skin,  or  of  cutting  the  tuber,  is  that  of  increasing  the 
moisture  loss,  which  seems  to  resiilt  in  a  greater  activity  of  the 
life  processes  of  the  plant,  thereby  inducing  an  earlier  germination. 

Practices  Compared. — While  the  foregoing  methods  of  hand- 
ling the  seed  from  the  first  crop  are  all  bona  fide  practices,  it  is 
but  fair  to  say  that  all  are  not  of  equal  importance  insofar  as 
their  use  is  concerned.  Practice  1  is  probably  much  more  gener- 
ally followed  by  the  growers  than  all  the  others  combined.  It 
is  believed,  however,  that  with  a  strict  observance  of  the  necessary 
precautions  a  combination  of  2,  3,  or  4  with  that  of  6  would  be 
preferable  to  that  of  1.  Number  5  is  only  feasible  where  cold 
storage  is  available  and,  as  j^et,  it  has  not  been  sufficiently  tested 
to  determine  its  real  value.  In  adopting  any  of  these  practices 
the  main  object  of  the  grower  is  to  shorten  the  rest  period  of  the 
seed  potatoes  and  to  secure,  as  nearly  as  may  be,  a  hundred  per 
cent  germination  from  those  that  are  planted. 

The  present  practice  of  planting  the  culls  or  unsalable  potatoes 
from  the  first  crop  should  be  discontinued,  as  it  is  not  possible  to 
secure  a  maximum  yield  from  potatoes  weighing  an  ounce  or  less. 
Much  better  results  would  be  secured  if  the  grower  were  careful 
to  select  tubers  ranging  from  I14  to  3  or  4  ounces  in  Aveight. 
Such  tubers  are  sufficiently  developed  to  furnish  the   necessary 


106  POTATO  PRODUCTION  IN  THE  SOUTH 

vigor  to  the  plante  they  produce  to  insure  a  good  crop,  p^o^^ded 
they  have  favorahle  groA^ng  conditions. 

Quality  of  Second  Crop  Seed. — It  is  not  generally  known, 
to  northern  growers  at  least,  that  Oklahoma  and  Arkansas  second 
crop  seed  potatoes  are  considered  superior  to  northern  grown  seed 
stock  when  only  once  removed  from  the  North,  This  class  of 
stock  is  kno^vn  as  "Junior  seed;"  that  is,  seed  stock  purchased,  we 
will  say,  in  Nebraska  in  the  fall  of  1919,  is  planted  for  an  early 
crop  in  1920;  the  seed  obtained  from  the  early  crop  is  planted 
for  a  fall  or  second  crop;  the  seed  from  this  second  crop  is  known 
as  Junior  seed.  When  such  seed  is  grown  another  year,  the 
second  crop  seed,  say  in  1921,  is  known  as  Senior  seed.  Senior 
seed  is  generally  considered  inferior  to  fresh  seed  from  the  North, 
and  it  is  not  extensively  used. 

Time  of  Planting  Fall  and  Second  Crop. — As  the  object  of 
growing  a  fall  crop  is  to  produce  potatoes  for  late  fall,  winter  or 
spring  consumption,  or  for  the  production  of  seed  for  the  ensuing 
year's  early  crop,  the  date  of  planting  is  largely  governed  by  the 
date  of  the  first  killing  frost  in  "the  autumn.  In  other  words, 
planting  is  delayed  as  long  as  it  is  possible  and  still  be  reasonably 
certain  of  a  sufficiently  long  grooving  period  to  permit  the  tubers  to 
reach  full  size,  or  at  least  to  make  a  fair  crop.  Full  maturity 
is  not  desired  in  the  case  of  the  second  crop.  A  study  of  the 
planting  dates  given  in  the  table  shows  that  they  extend  from 
June,  in  Delaware  and  Maryland,  to  October,  in  Florida. 

Yields. — As  a  rule,  the  yields  from  the  fall  or  second  crop 
are  not  as  large  as  from  the  early  or  late  crop,  except  when  the 
season  is  very  favorable  to  their  development,  in  which  case  they 
may  greatly  exceed  the  early  crop.  In  the  case  of  the  second 
crop,  large  yields  are  not  so  important  as  the  production  of  medium 
sized  tubers  of  high  quality  for  seed  purposes. 

POTATO    PRODUCTION    BY    STATES 

In  order  to  obtain  a  fairly  intimate  knowledge  of  the  extent 
and  importance  of  the  potato  crop  in  each  of  the  sixteen  southern 
states,  it  has  seemed  desirable  to  present  a  brief  summary  of  the 
industry  in  each  state.  It  is  obvious  that  in  such  a  discussion 
it  is  not  possible  to  enter  into  very  minute  details  concerning  the 
methods   practised  in  the   leading  producing   centres.      Further- 


POTATO  PRODUCTION  IN  FLORIDA 


107 


more,  cultural  ])ractices  are  discussed  in  the  chapter  devoted  to 
that  subject. 

While  first  hand  information  has  been  obtained,  through  per- 
sonal visitation  of  many  of  the  leading  producing  centres  in  the 
South,  claim  cannot  be  made  that  all  points  have  been  visited. 
It  has  therefore  been  necessary  to  rely  upon  such  information  as 
has  been  published  or  secured  through  correspondents.  The  data 
presented  are,  of  necessity,  taken  from  the  reports  of  the  Bureau 
of  Crop  Estimates. 

Potato  Production  in  Florida. — The  Florida  potato  crop  is  of 
interest  to  the  student  of  potato  culture,  as  well  as  to  consumers, 
from  a  number  of  standpoints.  In  the  first  place,  the  crop  in 
some  sections,  notably  in  the  Hastings  district,  is  grown  under 
some  conditions  entirely  different  to  those  encountered  in  any 
other  potato-producing  section  in  the  United  States  or  elsewhere 
and  in  the  second  place,  it  is  of  interest  to  the  consumer  because, 
outside  of  foreign  sources  such  as  the  Bermuda  and  Isle  of  Pines 
crop  it  is  the  first  large  commercial  section  to  supply  new  potatoes 
in  the  spring  to  northern  markets. 

Extent  of  the  Crop. — The  potato  crop  of  Florida  is  relatively 
small  as  compared  with  that  of  the  larger  potato-producing  states 
of  the  North,  or  for  that  matter  with  some  individual  counties  as, 
for  example,  Aroostook  County,  Maine.  On  the  other  hand,  the 
increase  in  potato  production  during  the  seasons  of  1917  and  1918, 
has  been  quite  marked,  as  "svill  be  noted  from  a  comparison  of  the 
yields  during  the  past  five  years  (1915  to  1919)  : 


1915,  12000  acres 

960,000  bu 

shels,  av.  yield  per  a 

ere  80  bushels 

1916,  15000    " 

1,110,000 

74        "       ,    increase  over  1915-15.6 

1917,  25000    " 

2,275,000 

91         "       ,        -136.9 

1918,  35000    " 

3,500,000 

100        "       ,        ' -264.6 

1919,  24000    " 

1,824,000 

"     ,     " 

'76        "      ,        '      -90.0 

Localities  Where  Grown. — The  chief  potato  producing  sec- 
tions in  Florida  are  located  in  St.  John  and  Putnam  counties, 
commonly  spoken  of  as  the  Hastings  district.  The  normal  potato 
average  of  this  district  is  around  11,000  acres,  but  in  1918  it 
was  variously  reported  at  from  13,000  to  15,000  acres.  Kissim- 
mee,  in  Osceola  County,  claimed  to  have  1800  acres  in  1918. 
Lesser  acreages  were  grown  in  the  vicinity  of  Plant  City  and 
Tampa.  A  considerable  potato  acreage  is  grown  in  the  territory 
surrounding   Lake    Okechobee,    known    as   the   Upper   Everglades 


108  POTATO  PRODUCTION  IN  THE  SOUTH 

region,  Moore  Haven  and  Okechobee  being  the  largest  production 
centres  of  tliis  section.  A  rather  small  acreage  is  grown  in  the 
vicinity  of  Miami  and  a  somewhat  larger  one  near  Vero.  Going 
north,  from  this  point,  a  considerable  acreage  may  be  found  in 
Volusia  County  near  DeLand.  This,  in  the  main,  may  Ijc  said 
to  cover  the  more  important  sections  of  the  state. 

Varieties  Grown  in  Florida. — Fortunately  for  the  potato 
industry  of  the  South  but  few  varieties  are  grown.  In  Florida, 
for  example,  the  leading  varieties  are  Spaulding  No.  4,  or  Spauld- 
ing's  Rose  as  it  is  more  generally  kno\\ni,  and  Triumph.  The 
Irish  Cobbler  is  grown,  to  a  slight  extent,  in  Lake  Okechobee  dis- 
trict. The  Triumph  is  grown  in  the  southern  half  of  the  state, 
and  the  Spaulding  No.  -i  in  the  northern  half.  The  latter  variety 
is  grown  in  the  Hastings  and  Kissimmee  areas  and,  to  a  slight  ex- 
tent, at  Plant  City;  but  elsewhere,  with  the  exception  of  Volusia 
County,  the  Triumph  is  the  leading  variety.  The  reason  for  this 
more  or  less  well  defined  demarcation  of  areas  in  which  these  two 
varieties  are  gro\m  is  not  quite  clear,  except  that  each  has  given 
best  satisfaction  in  the  areas  in  which  they  are  now  grown.  There 
is  a  possible  explanation,  however,  of  the  exclusion  of  Spaulding 
Xo.  4  from  the  southern  and  western  portion  of  the  state;  this 
variety  is  very  sensitive  to  a  check  in  its  growth  due  to  a  lack  of 
soil  moisture,  sucn  a  check  being  almost  certain  to  result  in  the 
tubers  germinating,  and  making  what  is  known  as  "second  growth" 
which  invariably  gives  knobby  tubers  and  a  large  percentage  of 
culls.     The  Triumph  zone  is  almost  entirely  a  non-irrigated  area. 

Potato  Production  in  Georgia. — The  Georgia  potato  crop  in 
1918  was  somewhat  less  than  half  that  of  Florida,  the  total 
yield  being  1,610,000  bushels,  with  an  average  acreage  produc- 
tion of  70  bushels. 

Production  Centres. — The  chief  commercial  production  centres 
are  the  Savannah  and  Cairo  districts;  the  former  being  much 
more  important. 

Variety  Grown. — The  Irish  Cobbler  is  the  most  extensively 
grown  variety  for  the  early  truck  crop. 

Potato  Production  in  South  Carolina. — The  1918  potato  cro]) 
of  South  Carolina  was  more  than  three  times  as  large  as  that  of 
the  average  for  the  years  1914  to  191G  inclusive,  and  over  twice  as 
great  as  that  of  1917,  thus  evidencing  the  response  of  the  growers 


POTATO  PRODUCTION  IN  VIRGINIA  109 

to  their  counti7's  call  for  a  larger  food  production  program.  The 
total  production  of  the  state,  however,  even  in  1918  is  relatively 
small,  (2,856,000  bushels),  but  as  it  is  practically  all  harvested 
as  an  early  crop,  it  does  have  an  economic  bearing  on  potato 
prices  during  the  period  in  which  the  crop  is  moved  to  market. 

Production  Centres. — The  chief  production  centres  are  located 
in  Beaufort  and  Charleston  counties  and  are  commonly  known  as 
the  Beaufort  and  Charleston  districts.  The  chief  shipping  points 
in  Beaufort  County  in  order  of  importance,  arc  Sheldon,  Port 
Koyal,  and  Beaufort.  In  Charleston  County  they  are  John's 
Island,  Charleston,  Meggett,  and  Yonge's  Island.  The  only  other 
point  from  \^'hich  any  considerable  shipment  was  made  in  1916 
was  that  of  Myrtle  Beach  in  Horry  (*ounty. 

Potato  Production  in  North  Carolina. — The  North  Carolina 
})otato  crop  is  of  considerably  greater  importance  than  that  of 
its  sister  state  to  the  south.  Based  on  its  average  production  for 
the  past  five  years,  (1914-1918),  it  occupies  28th  place  among  the 
states  of  the  Union.  The  1917  and  1918  crops  were  approximately 
41/)  and  41/4  million  bushels  respectively.  The  general  similarity 
of  conditions,  so  far  as  soil,  climate,  variety  grown,  and  general 
cultural  methods  practised  is  so  nearly  identical  to  that  of  South 
Carolina  as  to  make  repetition  unnecessary.  There  is,  however, 
one  feature  connected  with  the  North  Carolina  potato  crop  that 
is  somewhat  difi'erent  from  that  of  the  three  states  thus  far  dis- 
cussed; that  is,  that  a  considerable  percentage  of  the  crop  is  grown 
as  a  late  or  main  crop,  just  as  in  the  North.  This  is  due  to  the 
mountainous  character  of  the  western  portion  of  the  State,  which 
affords  very  similar  climatic  conditions  to  those  of  northern  regions. 

Production  Centres. — The  chief  early  potato  producing  centres 
are  located  around  Washington  in  Beaufort  County;  Newbern  in 
Craven  County;  Elizabeth  City  in  Currituck  County;  Calypso  in 
Duplin  County;  and  Mt.  Olivet  in  Wayne  County.  Elizabeth  City 
is  the  outlet  or  shipping  point  of  peninsula  shipments.  This 
point  and  Mt.  Olivet  were  the  heaviest  shipping  points  in  the 
state  in  1916. 

Potato  Production  in  Virginia. — Within  the  past  two  years 
Virginia  has  passed  from  the  11th  to  the  7th  largest  potato  produc- 
ing state  in  the  Union.  The  crop  of  Virginia  is  made  up,  even 
to  a  larger  extent  than  is  North   Carolina,  of  early  and  late  or 


110  POTATO  PRODUCTION  IN  THE  SOUTH 

main  crop  production  areas.  Larger  quantities  of  second  crop 
and  fall  potatoes  are  also  grown.  In  fact,  the  total  crop  is  diffi- 
cult of  analysis  as  to  the  relative  magnitude  of  the  early  or  truck 
crop  jjortion  of  the  crop  as  compared  with  the  late  or  main  and  the 
second  and  fall  crop.  As  nearly  as  it  is  possible  to  judge  from 
shipments,  the  early  crop  represents  approximately  50  per  cent 
of  the  total.  It  is  hardly  necessary  to  state  that  the  early  crop  is 
grown  in  the  coastal  plain  or  eastern  section  of  the  state,  and  that 
tne  second  and  fall  crop  is  also  produced  in  the  same  area.  The  late 
or  main  crop  is  grown  in  the  central  and  western  portions  of  the 
state  where  the  elevation  affords  similar  climatic  conditions  to 
those  described  in  North  Carolina. 

Potato  production  in  Virginia  reached  its  high-water  mark 
in  1!)15,  when  a  crop  of  1^1/2  million  bushels  was  harvested. 

Production  Centres. — The  two  generally  recognized  potato- 
producing  centres  in  Virginia  are  those  of  the  Norfolk  and  Eastern 
Shore  districts;  but  as  these  sections  are  made  up  of  more  than 
one  county,  they  represent  rather  large  territory,  which  can  per- 
haps be  better  considered  sectionally  or  by  counties.  The  Eastern 
Shore  of  Virginia  consists  of  two  counties,  Northampton  and 
Accomac.  Cape  Charles  is  the  principal  shipping  centre  of  North- 
am])ton  County ;  but  in  the  case  of  Accomac,  there  does  not  appear 
to  be  any  particular  or  outstanding  shipping  centre.  The  carload 
shipments  from  tliese  two  counties  in  1916  were  8,386  from  North- 
ampton and  6,485  from  Accomac.  The  Eastern  Shore  district 
is  easily  the  leading  early  potato-producing  section  in  the  United 
States  so  far  as  volume  is  concerned. 

The  Norfolk  district  includes  Norfolk  and  Princess  Anne 
counties.  Most  of  the  potatoes  are  grown  in  Norfolk  County,  of 
which  the  city  of  Norfolk  is  the  leading  shipping  centre.  In 
1916,  5,809  cars  were  shipped  from  this  county  as  against  221 
from  Princejis  Anne  County. 

Among  other  Virginia  centres  that  might  be  mentioned  are 
those  of  Toano  in  James  City  County,  from  which  343  carloads 
were  shipped  in  1916;  1,038  cars  from  Occohannock  Eiver  landings 
and  895  cars  from  Eastern  Shore  points,  by  boat,  to  Crisfield, 
Maryland. 

In  general  the  soil  and  climatic  conditions  of  the  trucking 
sections  of  Virginia  are  very  similar  to  those  in  North  and  South 
Carolina,   the   only   difference   being   that   the   season   is   just  a 


POTATO  PRODUCTION  IN  ALABAMA  111 

little  later.  The  soil  for  the  most  part  is  well  adapted  to  potato 
culture  and,  when .  properly  drained,  responds  quickly  to  good 
cultural  practices. 

Potato  Production  in  Maryland. — The  early  potato  crop  of 
Maryland  is  a  relatively  small  one  as  compared  with  Virginia. 
The  bulk  of  the  early  crop  is  grown  on  the  Eastern  Shore  of 
Maryland,  commonly  knoA\ai  as  the  Maryland  peninsula.  It  is 
simply  a  continuation  of  the  Eastern  Shore  of  Virginia  district. 

The  total  crop  of  the  state  for  the  past  five  years  including 
early,  late,  second  and  fall  crops,  averages  less  than  four  and  one- 
half  million  bushels.  In  1917  the  production  was  six  million 
bushels,  in  1918  about  four  and  one-quarter  million,  and  in  1919 
almost  five  and  one-sixth  million  bushels. 

Production  Centres.- — Worcester  County,  adjoining  Accomac 
County  in  Virginia,  is  the  chief  production  centre  with  a  total  of 
1197  carloads.  Baltimore  is  credited  with  2170  cars,  but  it  is 
quite  evident  that  a  considerable  percentage  of  these  shipments 
must  have  represented  trans-shipments  of  potatoes  arriving  in 
Baltimore  by  boat,  and  not,  as  might  l)e  inferred,  actual  production 
in  the  vicinity  of  the  city. 

Potato  Production  in  Delaware. — The  potato  crop  of  Dela- 
ware is  of  such  small  magnitude,  as  far  as  its  influence  on  the  total 
production  of  the  country  is  concerned,  as  to  be  almost  negligible. 
In  point  of  production,  Delaware  ranks  as  45th  state.  The  aver- 
age for  the  years  1915  to  1919  is  only  a  trifle  over  one  million 
])ushels.  The  total  shipments  in  1916  were  only  121  cars,  of 
which  Sussex  County  contributed  101  cars.  Nassau,  Selbyville, 
Frankford  and  Georgetown  in  Sussex  County,  and  Wyoming  in 
Kent  County  were  the  heaviest  shipping  points. 

According  to  the  Bureau  of  Crop  Estimates,  5  per  cent  of 
the  crop  was  harvested  in  June,  23  in  July,  21  in  August,  13  in 
September,  19  in  October,  and  IG  in  November. 

It  is  quite  evident,  from  the  above  data,  that  fully  50  per  cent 
of  the  crop  grovni  could  be  classed  as  late  or  main  crop  potatoes. 
The  Irish  Cobbler  is  the  favorite  early  variety,  and  a  red  skinned 
potato  of  the  Eose  group  as  a  late  variety. 

Potato  Production  in  Alabama. — In  point  of  production 
during  the  last  five  year  period  (1915-1919)  the  state  of  Alabama 
ranks  33rd.  The  average  production  during  this  period  was  nearly 
3  million  bushels.     The  1918  crop  was  63  per  cent  larger  than 


112  POTATO  PRODUCTION  IN  THE  SOUTH 

the  five  year  avora<,^o  or  1.8  million  bushels.  The  1911)  crop  shows 
a  decrease  of  nearly  27  per  cent  I'rom  that  of  the  1918  crop,  due 
wholly  to  a  curtailment  of  acrccige  as  a  result  of  vmsatisfactory 
prices  in  1918. 

Froduction  Centres.— The  chief  potato  production  centres  are 
located  in  Mobile  and  Baldwin  counties  in  the  southern  part  of 
the  state.  Mobile,  Theodore,  and  Dawes  are  the  chief  shipping 
points  in  Mobile  County,  and  Foley  in  Baldwin  County.  The 
area  planted  to  early  potatoes,  in  1916,  in  these  two  counties  was 
estimated  at  about  2000  acres.  No  large  growers  were  noted  in 
Mobile  County  in  1916.  The  maximum  acreage  observed  on  any 
farm  did  not  exceed  ten  acres. 

Potato  Production  in  Mississippi. — The  potato  crop  of  Mis- 
sissippi, like  that  of  Alabama,  is  a  comparatively  unimportant  one. 
The  average  production  of  the  state  for  the  past  five  years,  1914  to 
1918,  is  a  trifle  over  1.1  million  bushels.  It  ranks  as  44th  state 
in  volume  of  bushels  produced. 

Froduction  Centres. — Comparatively  speaking  one  can  hardly 
claim  any  real  centres  of  early  crop  production,  as  the  quantity 
shipped  is  almost  too  small  to  be  taken  into  consideration.  Adams 
and  George  counties  are  the  heaviest  producing  sections;  the  first 
representing  a  shipment  in  1916  of  35  cars,  and  the  latter  34. 
Natchez  is  the  leading  shipping  point  in  Adams  County  and  Evan- 
ston  in  George  County. 

Potato  Production  in  Louisiana. — One  of  the  most  interest- 
ing features  of  potato  ))roduction  in  Louisiana  is  the  fact  that  the 
growers  have  not,  as  in  most  of  the  other  southern  states,  centred 
on  a  single  commercial  variety.  While  the  Triumph  is  the  leading 
variety,  it  has  a  strong  competitor  in  a  variety  locally  known  as 
"Long  White"  wdiich  the  writer  believes  to  be  a  mem])er  of  the 
Burbank  group — probably  White  Star.  Another  point  of  interest 
is  the  remarkable  response  of  the  growers,  in  1918,  to  the  appeal 
for  a  larger  production  of  food  crops;  and  doubtless,  too,  as  a 
psychological  effect  of  the  high  prices  received  for  the  1917  crop. 
The  acreage  in  1918  was  over  111  per  cent  greater  than  the 
average  of  the  three  preceding  years  and,  in  point  of  production, 
the  crop  was  almost  three  times  as  large  or  4,345,000  as  compared 
to  the  three  year  average  of  1,551,000  bushels.  The  average 
per  acre  production  of  the  state  for  the  years  1915  to  1919  was 
07.1    bushels.     The    1919    production   was    1,600,000    bushels,    or 


POTATO  PRODUCTION  IN  LOUISIANA 


113 


a  trifle   over   2.3   per   cent  greater   than   the   previous   four   year 
average. 

Production  Centres. — In  by-gone  days  the  Alexandria  and 
Slireveport  districts  were  generally  recognized  as  the  leading  potato 
growing  sections;  but  in  1916,  a  personal  visit  revealed  the  fact 
that  the  Shreveport  district  had  long  ceased  to  produce  potatoes 
on  a  commercial  scale;  and  that  the  Alexandria  district  was  not 
as  important  as  had  been  supposed,  less  than  2,500  acres  being 
devoted  to  the  crop  in  that  season.  Some  rather  remarkable 
changes  in  acreage  have  taken  place  since  1917,  as  is  evidenced 
from  the  folloAving  data  on  the  1918  crop,  secured  from  the  Bureau 
of  Markets. 


Avoj-elles,    Parish    or    County 

East  Baton  Rouge,  Parish  or  Comity 
East  Feliciana,  Parish  or  County.. 

Iberia,    Parish   or   County    

Il)erville,   Parish   or   County    

LaFourche,  Parisli  or  County 

Plaquemines,  Parish  or  County  .... 

Point  Coupee,  Parish  or  County    .  . 
St.  John  Baptist,  Parish  or  County 

St.  Landry,  Parish  or  County    .... 

St.  Mary,  Parish  or  County    

Terrebonne,   Parish  or  County    .... 
West  Feliciana,  Parish  or  County.  . 


Total    of    14    counties.. 
Remaining    22    counties 

Total     


1.800  acres, 
L900  acres, 
1,500  acres, 
2,.S00  acres, 
L200  acres, 
17,500  acres, 

1,700  acres, 

2,650  acres, 
2,000  acres, 

1,200  acres, 

1,700  acres, 
1,600  acres, 

1,850  acres. 

38,n00  acres 
6,960  acres 


Triumphs 
Triumplis 
Triumphs 
Triumphs 
Triumphs 

Long  Whites  ( Burbanks 
probably ) 
Long         Whites         and 
Triumphs 
mostly    Triumplis 
Triumphs       and       Long 
Whites 
Triumphs       and       Long 
Whites 
mostly  Triumplis 
Triumphs       and       Long 
Whites 
mostly  Triumphs 


45,860  acres 


It  IS  interesting  to  note  the  very  large  acreage  in  LaFourche 
County,  amounting  as  it  does  to  almost  half  of  the  total  acreage 
of  the  14  counties,  and  considerably  over  a  third  of  the  acreage  of 
the  whole  state  as  here  given.  It  is,  however,  less  than  one-third 
of  the  acreage  reported  by  the  Bureau  of  Crop  Estimates,  which 
IS  9,140  acres  greater  than  the  above  data.  Such  a  discrepancy 
can  be  readily  accounted  for,  as  the  Bureau  of  Markets  data  proba- 
bly only  took  into  consideration  the  early  crop,  while  the  Crop 
Estimates  report  included  both  the  early  and  the  fall  crop. 

The  fact  that  two  varieties  are  grown  commercially  is  also  of 
interest  as,  outside  of  Florida,  it  is  the  exception  rather  than  the 
8 


114  POTATO  PRODUCTION  IN  THE  SOUTH 

rule.  It  is  especially  interesting  to  note  that  the  Long  White 
(White  Star)  variety  is  largely,  if  not  almost  exclusively  grown, 
in  the  southeastern  part  of  the  state,  or  the  region  which  might 
be  regarded  as  tributary  to  New  Orleans.  It  simply  illustrates  the 
fact  that  the  Long  Wliite  variety  is  either  better  adapted  to  the 
soil  and  climatic  conditions  of  this  region,  or  that  the  growers 
are  catering  to  a  distinct  preference  on  the  part  of  tlie  trade,  for 
white   skinned   varieties. 

Potato  Production  in  Texas.-^Texas  ranks  as  34th  state  in 
point  of  production.  The  average  bushels  produced  during  tht 
five  years,  1915  to  1919,  is  2,917,200  with  a  maximum  production 
in  1919  of  3,790,000.  A  comparison  of  the  acreage  production 
of  Texan  potato  fields  with  those  of  other  southern  states,  shows 
that  the  yield,  60.8  bushels,  is  less  than  that  of  any  of  them. 
The  reason  for  such  low  yields  is  that  the  crop  is  a  rather  uncertain 
one,  owing  to  its  being  subjected  to  such  variable  and  trying 
climatic  conditions. 

Viewed  in  its  entirety,  the  potato  crop  of  Texas  is  comparatively 
insignificant  when  the  size  of  the  state  is  taken  into  consideration ; 
yet  there  are  a  few  localities  in  which  the  crop  is  a  fairly 
important  one. 

Production  Centres. — The  chief  commercial  potato  centres  in 
Texas  are  the  Wharton  and  Eagle  Lake  districts,  located  in  Colo- 
rado and  Wharton  Counties  respectively;  Simonton  and  Fulshear 
in  Fort  Bend  County:  and  Brownsville  and  San  Benito  in  Cameron 
County.  The  car  lot  shipments  in  1916  from  Eagle  Lake  were 
441  ;  Wharton  343 ;  Egypt  and  Glen  Flora  in  the  same  county 
103  and  58;  Simonton  193;  Fulshear  41;  Brownsville  101  and 
San  Benito  50.  The  total  shi])ments  reported  by  the  Bureau  of 
Markets  in  1916,  1917  and  1918  were  1,649,  1,671,  and  2,312 
cars  respectively. 

Potato  Production  in  Oklahoma. — The  average  production 
of  potatoes  in  the  state  of  Oklahoma  during  the  years  1915  to  1919 
was  less  than  21/^  million  bushels  or  to  be  specific  2,496,200  bushels. 
The  average  yield  per  acre  was  62.7  bushels  or  the  second  lowest 
in  the  Union.  If  judged  by  car  lot  shipments,  the  potato  crop 
of  Oklahoma  would  not  take  very  high  rank  as  a  commercial  indus- 
try. The  shipments  for  1916,  1917  and  1918  were  1,424,  625, 
and  349  respectivjfely.  These  figures  are  not  substantiated  by 
those  of  the  Bureau  of  Crop  Estimates,  which  show  more  than  a 
331/i  per  cent  increase  in  the  1917  crop  over  that  of  1916;  despite 


POTATO  PRODUCTION  IN  ARKANSAS  115 

this  fact  the  shipments  were  over  50  per  cent  less.  It  is  presuma- 
ble that  the  1917  and  1918  Bureau  of  Markets  data,  issued  under 
date  of  January  28,  1919,  does  not  represent  as  complete  a  record 
of  the  car  lot  movements  as  in  1916.  The  crop  movement  is  be- 
tween May  25  and  July  15. 

ProducHon  Centres. — The  heaviest  production  centres  are  lo- 
cated in  Muskogee,  La  Flore  and  Sequoyah.  Fort  Gibson,  Webbers 
!Falls,  Wybark  and  Muskogee  are  the  heaviest  shipping  points  in 
Muskogee  County;  Spiro  in  La  Flore;  and  Gore,  Vian  and  Mul- 
drow  in  Sequoyah  County.  The  total  car  lot  shipments  from  each 
of  these  counties  is  as  follows :  Muskogee  7,811,  La  Flore  2,671,  and 
Sequoyah  192.  Of  the  781  cars  shipped  from  Muskogee  County, 
461  are  credited  to  Fort  Gibson,  Avhich  is  the  centre  of  the  com- 
mercial potato  area  and  is  located  in  the  Arkansas  River  Valley.  A 
considerable  proportion  of  the  crop  in  this  section  is  grown  on  the 
fertile  river  bottom  lands,  which  for  the  most  part  consist  of  a 
light  sandy  loam  well  adapted  to  potato  culture. 

It  is  interesting  to  note  that  in  1891  the  horticulturist  of  tlie 
State  Experiment  Station,  0.  M.  Morris  ^  stated  that  the  largest 
commercial  potato  growing  district  in  Oklahoma  at  that  time  was 
confined  to  the  valley  of  the  North  Canadian  river  in  Pottawatomie 
County.  The  1916  shipments  from  this  county  were  62  cars,  57 
of  which  were  from  Shawnee  and  five  from  Dale.  This  affords  an 
excellent  illustration  of  how  production  centres  may  shift  from 
year  to  year,  or  from  decade  to  decade.  The  shifting  of  truck 
crop  centres  is,  perhaps,  more  largely  confined  to  the  South  than 
to  the  North ;  and  this  is  particularly  true  with  respect  to  the 
potato  crop  which,  outside  of  a  few  well  recognized  districts,  is 
more  or  less  of  a  catch  crop  ^Wth  the  trucker,  and  is  subject  to 
wide  fluctuations  in  acreage,  according  to  whether  prices  rule 
high  or  low. 

Potato  Production  in  Arkansas. — As  a  potato  growing  state 
x^rkansas  stands  as  35th  state  in  point  of  production.  The  aver- 
age for  the  past  five  years,  1915  to  1919,  is  nearly  two  and  three- 
quarter  million  bushels,  (2,709,000),  and  the  average  yield  per 
acre  for  the  same  period  is  72.1  bushels.  The  total  car  lot  ship- 
ments reported  for  the  state  in  1916  were  only  537.  It  is  evident 
therefore  that,  from  a  commercial  standpoint  at  least,  it  exerts 
little  influence  on  the  outside  markets. 

Production  Centres. — Commercially  speaking  there  is  but  one 
production  centre  worthy  of  consideration.     This  is  the  district 


116  POTATO  PRODUCTION  IN  THE  SOUTH 

surrounding  Fort  Smith  in  Sebastian  County,  from  which  383  of 
the  537  cars  were  shipped.  Of  this  number  313  were  moved 
from  Fort  Smith.  Other  points  that  might  be  mentioned  are 
Alma,  in  Crawford  County,  30  cars;  Booneville,  in  Logan  County, 
25  cars;  Charleston,  in  Franklin  County,  23  cars;  and  Rob  Roy, 
in  Jefferson  County,  18  cars.  It  is  quite  ap])arent  from  these 
figures  that  the  real  commercial  area  of  potato  produc- 
tion is  in  the  vicinity  of  Fort  Smith.  The  Fort  Smith  figures  may, 
however,  be  misleading;  it  is  altogether  probable  that  they  include 
a  consideral)le  portion  of  Oklahoma-grown  potatoes,  as  the  river 
bottom  lands  on  both  sides  of  the  Arkansas  river  are  largely 
planted  to  potatoes  in  this  })articular  locality. 

In  some  respects  the  soil  and  the  general  lay  of  the  land,  both 
in  Arkansas  and  Oklahoma  in  the  Fort  Smith  district,  is  ideal 
for  potato  culture.  The  sandy  loam  soil  is  of  alluvial  origin,  and 
is  easily  kept  in  good  physical  condition  provided  any  reasonal:)le 
attention  is  given  to  the  maintenance  of  a  good  supply  of  organic 
matter.     The  Trium])h  is  the  leading  early  variety. 

Potato  Production  in  Tennessee. — Based  on  its  five-year 
average,  Tennessee  stands  6th  in  point  of  production  of  the  six- 
teen states,  regionally  grouped  as  southern  states  by  the  Bureau 
of  Crop  Estimates.  It  ranks  28th  among  the  48  states  of  the 
Union,  with  a  total  average  production  during  the  years  1915  to 
1919  of  3,525,600  bushels,  and  an  average  yield  per  acre  of 
79.4  bushels.  As  57  per  cent  of  the  crop  is  harvested  after 
September  1,  it  is  safe  to  assume  that  the  potato  is  quite  largely 
grown  as  a  late  or  main  crop,  or  a  fall  crop  rather  than  as  an 
early  or  truck  crop. 

Production  Centres. — The  heaviest  shipping  section  is  found 
in  Gibson  County,  from  which  some.  576  carloads  were  moved  in 
1916.  Lauderdale  County  is  next  Avith  133  cars.  The  leading 
shipping  stations  in  Gibson  County  are  Gibson  198,  Milan  156, 
Humboldt  130,  Fruitland  60,  Medina  20  and  Bradford  12.  Halls 
is  the  leading  shipping  point  in  Lauderdale  County.  The  Cum- 
berland Plateau  in  Cumberland  County  offers  possibilities  for  the 
development  of  a  considerable  industry  in  the  production  of  late 
or  main  crop  potatoes.  Second  crop  potatoes  are  also  grown  quite 
extensively  in  some  parts  of  the  state.  Columbia  is  the  centre 
of  the  second  crop  potato  industry. 

Potato  Production  in  Kentucky. — The  potato  crop  in  Ken- 
tucky ranks  21st  in  point  of  production  with  an  average  of  over 


POTATO  PRODUCTION  IN  WEST  VIRGINIA  117 

5I/2  million  bushels.  The  response  of  the  Kentucky  farmer  to 
the  appeal  for  a  hirger  crop  of  potatoes,  as  well  as  other  food  crops, 
is  well  showai  by  the  increased  acreage  in  1918.  A  comparison 
of  the  1918  acreage  with  that  of  1915  shows  a  47  per  cent  increase 
in  favor  of  1918.  If  the  necessary  data  were  available  it  could 
])robably  be  shown  that  the  potato  crop  of  Kentucky,  like  that  of 
Tennessee,  is  very  largely  made  up  of  late,  second  and  fall 
crop  varieties. 

Production  CeJifrcs. — Jefferson  County,  Kentuck}',  is  by  all  odds 
the  leading  potato-producing  centre,  as  it  includes  the  well-known 
Louisville  district.  The  total  car  lot  movements  reported  for 
the  state  by  Froelich,-  for  1916,  was  1,399,  and  of  this  number 
Jefferson  County  is  credited  Avith  1356.  Louisville  and  St.  Mat- 
thews are  the  two  leading  shipping  centres  with  556  and  326 
car  lots  respectively;  Lyndon  shipped  163;  O'Bannon  117: 
Buechel  115;  Prospect  34;  Jeffersontown  33;  Anchora;^e  20; 
and  Lakeland  2. 

Potato  Production  in  West  Virginia. — While  the  state  of 
AVest  Virginia  is  geographically  included  in  the  southern  group  of 
states,  it  naturally  ])elongs  to  the  northern  or  late  crop  group. 
The  Monthly  Crop  Eeport  of  the  Bureau  of  Crop  Estimates  for 
November,  1016,  p.  116,  gives  the  percentage  of  the  crop  harvested 
per  month  as  1  per  cent  in  June;  7  in  July;  16  in  August;  36  in 
September;  37  in  October,  and  4  in  November.  It  is  thus  seen 
that  less  than  25  per  cent  of  the  acreage  planted  is  harvested 
as  an  early  crop.  The  average  yield  during  the  years  1915  to 
1919  was  over  5I/4  million  bushels,  and  the  yield  per  acre  99.3 
bushels.     In  relative  importance  West  Virginia  ranks  22nd. 

In  discussing  the  comparative  importance  of  the  potato  croji, 
Dacy  ^  says : 

"It  will  be  noted  that  the  area  devoted  to  the  potato  crop    (in  1909) 

averages  less  than  half  an  acre  to  the  farm The  only  counties  which 

ship  their  product  outside  of  the  state  to  any  extent  are  those  lying  along 
the  Ohio  River.  Their  surplus  goes  to  the  markets  of  Pittsburgh,  Penn- 
sylvania; and  to  Cincinnati  and  Columbus,  Ohio.  Even  if  every  bushel 
produced  was  kept   at   home,  we  would   still  have   to   import   from   other 

states   enough  to  feed   our  own  people There   seems   to  be   no   valid 

reason  why  West  Virginia  should  depend  upon  the  farmers  of  other  states 
to  fiirnish  such  a  large  share  of  the  potatoes  consumed  hy  her  people,  when 
there  are  thousands  of  acres  of  land  within  her  borders  that  are  splendidly 
adapted  to  the  growth  of  this  crop." 

The  physical  aspects  of  the  state  are  such  that  one  can  ea.^ily 
find  climatic  and  soil  conditions  admirably  suited  to  the  growing 


118  POTATO  PRODUCTION  IN  THE  SOUTH 

of  either  an  early  or  a  late  crop;  the  range  in  altitude  varies 
from  260  to  4,860  feet,  thus  affording  at  the  higher  altitude,  say 
1,800  to  3,000  ft.,  climatic  conditions  admirably  adapted  to  the 
production  of  a  late  crop,  which  could  be  marketed  for  table  or 
seed  stock,  according  to  where  it  was  produced  and  the  variety  grown. 
Production  Centres. — Strictly  speaking,  there  are  no  well  de- 
fined potato  production  centres  in  the  state,  unless  one  might 
choose  to  consider  those  counties  bordering  the  Ohio  Eiver,  some 
of  which  grow  a  good  many  Early  Ohio  for  the  Pittsburgh,  Cincin- 
nati and  Columbus  markets.  These  are  dug  early  and,  as  a  rule, 
are  at  once  shipped  to  market.  The  Bureau  of  Markets  reports 
that  only  59  cars  of  the  1916  crop  were  shipped  from  points 
of  production. 

QUESTIONS    ON   THE   TEXT 

1.  What  are  the  chief  points  of  difference  hetween  potato  jjrochiotion  in 

the  South  and  in  the  North? 

2.  How  many  crop  periods  are  there  in  the  South?     What  are  they  called? 

3.  Into  how  many  geoijraphical  sections  has  the  Bureau  of  Crop  Estimates 

divided  the  United  States?     Name  them. 

4.  Name  the  southern  States. 

.').  What  proportion  of  the  1920  potato  crop  did  the  South  produce? 

6.  Why  does  the  southern  potato  crop  command  a  hetter  a  price,  as  a  rule, 

than  the  northern  ? 

7.  What  is  the  relative  importance  of  the  early  crop  to  that  of  the  late 

and  fall  crops? 

8.  In  which  portion   of  the  South  is  the  percentage  of  early  to  late  or 

fall  crops  greatest?     ^lention  some  of  the  States. 

9.  Is  potato  production  in  the  South  capable  of  much  expansion?     Give 

reasons. 

10.  What  are  the  chief  advantages  to  the  grower   of   being  located   in   a 

production  centre? 

11.  Why  is  the  southern  grower  more  dependent  upon  active  selling  than 

the  northern  grower? 

12.  What  are  some  of  the  conditions  that  are  generally  regarded  as  being 

favorable  to  the  production  of  an  early  crop  of  potatoes? 

13.  Name  some  of  the  leading  commercial  centres  of  potato  production. 

14.  ^^'^ly  are  sandy  loam  soils  preferred  for  early  crops? 

15.  What  are  the' varieties  chiefly  grown  for  the  early  crop? 

IG.  From  what  localities  does  the  southern  grower  obtain  his   seed?     At 
what  time  of  year? 

17.  Throughout  what  months  is  the  early  crop  planted? 

18.  What  is  one  of  the  chief  risks  encountered  in  growing  an  early  crop? 

19.  In  what  particular  portions  of  the  South  are  late  or  main  crop  potatoes 

grown  ? 

20.  What  are  the  chief  points  of  difference  between  the  fall  crop  and  the 

late  crop? 

21.  Of  what  does  the  fall  crop  proper  consist? 

22.  W^hat  is  meant  by  second  crop  potatoes? 

23.  In  what  portions  of  the  South  are  fall  crop  potatoes  usually  grown? 

24.  What  varietiea  are  grown  for  fall  crop  production? 


QUESTIONS  ON  THE  TEXT  119 

25.  What  is  the  origin  of  the  White  McCormick?     Is  it  as  good  as  the 

McCormick  ? 

26.  What  are  the  sources  of  seed  supply  for  the  fall  crop? 

27.  What  classes  of  varieties  are  included  in  second  crop  production? 

28.  Within  the  strict  meaning  of  the  term  '"second  crop  potatoes"  what 

should  it  include? 

29.  What  is  the  source  of  seed  supply  where  the  Irish  Cobblers  are  grown? 

30.  Describe  practice  Xo.   1.     Why   is   it  so   important? 

31.  Describe  practice  No.    2   and    compare   with   No.    1. 

32.  Describe  practices  Nos.  3  and  4. 

33.  Describe  practice  No.  5. 

34.  Describe  practice  No.  6  and  give  its  relation  to  the  others. 

35.  Is  the  present  practice  of  using  the  culls  a  desirable  one?     Give  reasons. 

36.  What  should  be  the  determining  factor  as  regards  the  date  of  planting 

fall  or  second  crop  potatoes? 

37.  Why  is  it  desirable  to  delay  planting  as  long  as  possible? 

38.  Is  full  maturity  desired  in  the  second  crop?     Give  reasons. 

39.  How  does  the  yield  from  fall  or  second  crop  potatoes  compare  with 

that  of  the  early  crop? 

40.  Of  what  particular  interest  is  the  Florida  potato  crop  to  the  student 

of  potato  culture  and  the  consumer? 

41.  What  varieties  are  grown?     Give  portions  of  Florida  in  which  grown. 

42.  What  variety  does  the  Georgia  trucker  grow? 

43.  How   does   the    1918   crop   in    South    Carolina   compare    with    that    of 

1914  to  1917? 

44.  How    docs    the    North    Carolina    potato    crop    compare    with    that    of 

South  Carolina? 

45.  In  what  respect  does  North  Carolina's  potato  crop  differ  from  that  of 

the  three  preceding  states? 

46.  What  position  does  Virginia  hold  as  a  potato  producing  state? 

47.  In  what  parts  of  the  state  are  the  crops  produced? 

48.  Of  what  importance  is  the  early  potato  crop  in  Maryland  as  compared 

with  that  of  Virginia? 

49.  Is  the  potato  crop  of  Delaware  of  much  relative  importance?     What 

position   does  it  occupy? 

50.  What  was  the  average  production  of  Alabama  for  the  years   1915  to 

1919  inclusive? 

51.  What  is  the  rank  of  Mississippi  as  a  potato  producing  state? 

52.  What   is   one    of   the   interesting   features   about  potato    production    in 

Louisiana? 

53.  What  varieties  are  grown? 

54.  What  is  the  average  per  acre  production   for  the  state  as   a   whole? 

55.  Name   the   chief   production   centres.      Which    is    the   most   important? 

56.  Where  is  the  Long  White    (White  Star)    variety  most  largely  grown?  • 

57.  W^hat  was  the  average  potato  production  of  Texas  during  the  years 

1915-1919  inclusive? 

58.  What  record  does  she  hold  in  production  per  acre? 

59.  What  reasons  are  assigned  for  the  low  yield? 

60.  What  are  the  chief  commercial  centres"? 

61.  What   was    the    average    production    in    Oklahoma    for    1915    to    1919 

inclusive  ? 

62.  What  rank  does  she  hold  in  production  per  acre? 

63.  During  what  period  is  the  crop  moved  to  market? 

64.  What  is  the  rank  of  Arkans'as  in  point  of  production? 

65.  What  is  the  leading  variety? 


120  POTATO  PRODUCTION  IN  THE  SOUTH 

(U).   What  is  the  rank  of  Tennessee  in  point  of  produetio]!  both  in  tlie  South 

and  in  the  United  States? 
07.  A\  hat  ])erwntajj;e  of  tlie  crop  is  liarvested  after  September? 
lis.  Of  what  importance  is  the  Kentucky  potato  crop? 
()!».  What  are  the   leading  production  centres? 

70.  Of  what  importance  from  an  early  crop  standpoint  is  tlie  ^^■csl  Virginia 

potato   industry? 

71.  What  does  Dacy  .say  about  the  potato  crop  of  the  stale? 

72.  What  are  the  leading  production  centres? 

QUESTIONS   SUGGESTED   BY  THE  TEXT 

1.  tlow     many    crop    periods    in    your    region?     What    are    tlie    dates    of 

planting  ? 

2.  To  what  geograpliical  section  does  your  region  belong? 

3.  What  other  states  are  in  it? 

4.  ^^'llat  varieties  are  most  grown   in  your   region? 

5.  What  are  the  most  noted  production  centres  in  your  state? 

t).  How  do  these  compare  with  othei-  centres  in  the  United  States? 

References  Cited 

1.  Dacy,  A.  L.     1!)13.     Potato  Culture  in  West  Virginia.     11'.   l'«.  Exp.  tSlu. 

Bill.  140:  4,  S. 

2.  Froei.ich,   p.      IDIG.      Car-lot    Shipments    of    Fruits   and    Vegetables    in 

the  United  States  in  1916.     L.  >S'.  Dipt.  Agr.  Bui.  61)7,  June,  1916. 
:3.  Morris,  O.  M.     1891.     The  Potato  Crop.     Okla.  Exp.  tita.  Bui.  52:   3. 


CHAFTER  X 
POTATO  PRODUCTION  IN  THE  NORTH  AND  WEST 

In  the  preceding  chapter,  the  early  or  truck  crop  potato- 
producing  sections  in  the  South  were  considered  hoth  with  respect 
to  the  extent  of  the  crop  grown  as  compared  with  the  total  crop 
of  the  United  States  as  well  as  to  the  relative  importance  of  the 
crop  in  each  state.  It  was  shown  that  the  16  states  geograi)hically 
considered  as  belonging  to  the  South  only  producecl  a  little  over 
15  per  cent  of  the  total  crop.  When  it  is  remembered  that  this 
percentage  includes  all  the  early,  late  and  fall  crop  of  potatoes 
grown  in  the  South,  the  significance  of  the  comparison  and  the 
relative  importance  of  ])otato  production  in  the  North  and  West 
becomes  at  once  apparent. 

The  Potato  Essentially  a  Northern  Crop. — While  the  pro- 
duction of  late  or  main-crop  potatoes  is  not  entirely  confined  to 
the  North,  it  is  in  a  commercial  sense  very  largely  restricted  to 
the  northern  tier  of  states.  This  is  by  no  means  due  to  an 
accidental  circumstance,  but  rather  to  a  direct  recognition  of  the 
fact  that  the  potato  is  essentially  a  cool-loving  plant;  it  there- 
fore thrives  best  where  the  summer  temperatures  are  relatively 
low  and  where  the  ra-infall  is  sufficient  to  keep  the  plants  in  an 
active  stage  of  growth  throughout  the  season.  Such  climatic 
conditions  are  quite  generally  found  in  the  northern  part  of  the 
United  States  and  Canada,  and  in  some  of  the  more  elevated  por- 
tions of  the  South  and  West. 

Altitude,  as  well  as  latitude,  is  an  important  climatic  determin- 
ing influence  so  far  as  temperature  is  concerned,  and  must  be 
reckoned  with  in  the  consideration  of  the  suitability  of  a  given 
region  to  any  particular  crop. 

Confirmation  of  these  statements,  insofar  as  their  application 
to  the  late  potato  crop  is  concerned,  is  not  lacking  as  one  has  only 
to  call  attention  to  the  leading  potato-producing  states,  such  as 
New  York,  Minnesota,  Wisconsin,  Michigan,  Maine  and  Pennsyl- 
vania to  partially,  at  least,  prove  the  truth  of  this  assertion. 
The  average  production  of  these  6  states,  during  the  years  1915  to 
1919,  was  over  43.1  per  cent  of  the  total  crop  of  the  United  States. 

121 


122  POTATO  PRODUCTION  IN  NORTH  AND  \VEST 

Market  is  Another  Factor. — It  would  be  misleading,  as  well 
as  unjust,  however,  to  other  equally  as  well  favored  states,  climati- 
cally at  least,  to  assume  that  this  large  production  was  Avholly  due 
to  exceptionally  favorable  soil  and  climatic  conditions.  There  is 
another  factor  which  determines  to  a  very  large  extent — in  fact, 
it  may  be  considered  the  sole  limiting  factor  in  many  sections  of 
the  United  States;  this  factor  is  that  of  proximity  to  market  or 
to  the  large  consuming  centres.  The  potato  is  a  bulky,  and  rela- 
tively cheap  selling  food  product,  and  on  that  account  there  is 
not  a  sufficient  margin  between  the  cost  of  production  and  the 
selling  price  of  the  crop  to  permit  of  the  absorption  of  a  very 
heavy  transportation  charge.  This  limiting  factor  is,  therefore, 
responsible  for  the  relatively  light  production  of  the  eleven  far- 
western  states.  The  production  of  these  eleven  states  for  the 
years  1915  to  1919  has  averaged  just  a  trifle  under  14  per  cent  of 
the  total  crop  of  the  United  States.  If  one  attempted  to  judge 
the  adaptability  or  suitability  of  the  various  states,  in  this  country 
or  in  foreign  ones,  for  the  production  of  potatoes  solely  by  the 
extent  of  the  crop  produced,  they  would  very  likely  form  an 
erroneous  opinion  or  arrive  at  an  entirely  wrong  conclusion  regard- 
ing the  real  causes  of  heavy  or  light  production. 

Two  Important  Factors. — If  an  intelligent  understanding 
of  the  subject  is  to  be  reached,  one  must  consider  the  following 
two  factors:  (a)  average  production  per  acre,  and  (1))  the  produc- 
tion cost  per  bushel.  These  two  factors  are,  of  course,  largely 
determined  by  the  progressiveness  of  the  growers  as  regards  their 
cultural  practices  and  the  care  they  exercise  in  the  production 
and  use  of  good  seed  stock.  A  comparison  of  the  average  acre 
production  of  the  six  largest  northern  potato-producing  states 
with  that  of  the  eleven  far-western  states  for  the  five-year  period, 
1915  to  1919,  shows  that  the  former  produced  only  90.3  bushels 
per  acre,  while  the  latter  averaged  133.3  bushels  or  an  increase  of 
43  bushels.  It  is  evident,  therefore,  that  the  six  heavy  producing 
northern  states  do  not  enjoy  any  special  advantage  as  regards 
climate  or  soil.  The  real  explanation  of  their  large  production 
is  that  of  proximity  to  large  consuming  centres. 

Late  or  Main  Crop  Production  Centres. — Potato  production 
in  the  North  and  West  is  not  so  generally  confined  to  distinctive 
production  centres  as  in  the  South.  There  are,  however,  certain 
well  known  sections  which  are  generally  recognized  the  country 
over  as  important  potato-producing  areas.       These   sections'  are 


AROOSTOOK  COUNTY,  MAINE  123 

Aroostook  County,  Maine;  Long  Island  and  western  New  York; 
Monmouth  County,  jSTew  Jersey;  Waupaca  and  Stevens  Point, 
Wisconsin ;  the  Eed  Eiver  Valley  in  Minnesota  and  North  Dakota ; 
the  Kaw  (Kansas  River)  Valley  in  Kansas;  Greeley,  San  Luis 
Valley,  Carbondale  and  Montrose  districts  in  Colorado;  the  Idaho 
Falls  and  Caldwell  districts  in  Idaho;  the  Yakima  Valley  in 
Washington;  and  the  Stockton  district  in  California.  While  the 
above  localities  are  the  more  "widely  known  potato  production  cen- 
tres, they  do  not  necessarily  represent  all  of  the  important  sections. 
In  fact,  outside  of  Aroostook  County,  Maine,  western  New  York, 
and  Greeley,  Colorado,  there  are  a  number  of  other  districts  such 
as  southern  New  Jersey,  northeastern  Ohio ;  the  central  and  north- 
ern portion  of  the  lower  peninsula  of  Michigan,  and  many  others 
in  which  potatoes  are  produced  on  a  much  larger  scale  than  in 
some  of  the  better  known  areas  mentioned. 

Aroostook  County,  Maine. — The  state  of  Maine  has  long 
enjoyed  the  distinction  of  having  within  its  borders  a  county  that 
lu'oduces  on  the  average  more  potatoes  annually  than  all  but  the 
six  leading  states,  of  which  Maine  herself  is  the  fifth  in  point  of 
production.  It  is  probably  not  so  well  known  that  the  area  of 
Aroostook  County  is  almost  equal  to  that  of  the  Avhole  state  of 
Massachusetts  and  that,  notwithstanding  its  large  average 
annual  production  of  potatoes,  I7I/2  million  bushels,  less 
than  one-fourth  of  the  land  in  the  county  has  been  brought  under 
cultivation.  One  may  well  inquire  into  the  reason  for  this  seem- 
ingly large  development  of  commercial  potato  production  in  this 
somewhat  remote  market  region  of  the  United  States.  The  most 
logical  reasons  which  present  themselves  are  that  the  soil  and 
climatic  conditions  are  extremely  favorable  to  the  potato  crop; 
the  climate  is  too  cool  for  the  successful  production  of  corn  or 
other  cultivated  cash  crops,  hence  the  farmers  have  come  to  regard 
the  potato  as  their  chief  agricultural  money  crop;  and  to  look 
upon  grain  and  hay  as  merely  necessary  evils  in  the  practice  of  a 
safe  and  economic  crop  rotation  system. 

Soils. — The  soils  of  Aroostook  County  are  of  glacial  origin, 
but  are  not  thought  to  have  been  transplanted  very  far.  They  are 
mostly  derived  from  the  shaly  Aroostook  limestone,  which  underlies 
a  large  portion  of  this  area.  West  over  and  EoAve'^  classified  the 
soils  derived  from  the  unmodified  glacial  drift  into  eight  distinct 
types,  the  most  important  of  which  is  the  caribou  loam.  This 
type  of  soil  is  especially  suited  to  the  production  of  potatoes. 


124 


POTATO  PRODUCTION  IN  NORTH  AND  WEST 


Climatic  Conditions. — The  climatic  coiidit  ions  that  i)rovail  in 
Aroostook  County  vary  consiclerabl}'  from  those  which  ol)taiii  in 
the  southern  part  of  the  state.  The  temperature  is  much  hjwer 
in  the  winter  and  does  not  rise  as  high  in  the  summer;  the  rainfall, 
while  not  alwa^ys  as  copious  in  the  gro^^^ng  season,  is  usually  more 
evenly  distributed ;  and  it  is  seldom  that  the  potato  crop  of  Aroos- 
took suffers  very  seriously  from  either  heat  or  drought.     These  two 


Fig.  5S 


,h  Cobblers  just  coming  into  bloom. 


factors — heat  and  drought — exert  a  much  more  marked  inlhiciice  on 
tuber  production  than  we  are  wont  to  consider. 

Varieties  Grown. — The  leading  commercial  varieties  grown  in 
Maine  are  the  Irish  Cobbler  and  the  Green  Mountain.  In  the 
case  of  the  latter  variety,  it  is  supposed  to  include  the  members 
of  the  group,  such  as  the  Gold  Coin,  Snow,  Norcross,  etc.  The 
Irish  Cobbler  is  groM-n  both  for  seed  and  table  purposes,  wliih? 
the  Green  Mountain  is  grown  almost  exclusively  for  table  use.  In 
addition  to  these,  the  following  varieties  are  grown  for  seed  pur- 
poses as,  for  example,  the  Spaulding  No.  4,  American  Giant, 
Triumph,  Early  Ohio,  Early  Eose,  and  Quick  Lunch.  The  last 
three  varieties  arc  sparingly  grown  by  a  few  seed  growers. 


AROOSTOOK  COUNTY,  ]\IAINE 


125 


Potato  Blossoming. — In  no  other  section  of  the  United  States 
yet  visited  by  tlie  writer  does  tlie  potato  plant  bloom  as  freely 
as  m  northern  Maine.  The  reason  for  tliis  is  tliat  tlie  plants 
rarely  sirlfer  a  clicek  in  tlieir  growtli  due  to  lieat  or  drought 
during  the  period  in  Avliicli  tlie  blossoms  are  developing.  As  a 
result  of  these  favorable  conditions,  many  potato  fields  in  northern 
Maine  have  the  appearance  of  an  immense  flower  garden   (Figs. 


Fig.  59. — A  field  of  Irish  Cobblers  in  full  bloom.    Aroostook  Co.,  Me. 

58  and  59).     The  Irish  Cobbler  and  the  Green  Mountain  varieties 
are  especially  free  bloomers. 

On  account  of  the  favorable  climatic  and  soil  conditions  in 
Aroostook  County,  Maine,  the  United  States  Department  of  Agri- 
culture has  conducted  some  rather  extensive  potato  experiments  in 
this  section  since  1911.  At  present,  practically  all  of  the  breeding, 
selection,  seed  development  and  varietal  testing  are  located  on 
Aroostook  Farm,  Presque  Isle,  Me.  (Fig.  60.)  (Aroostook  Farm 
is  a  State  Experimental  Farm  operated  by  the  Maine  State 
Experiment  Station). 


126 


POTATO  PRODUCTION  IN  NORTH  AND  WEST 


Production  Centres  in  Aroostook  County. — While  the  county 
is  usually  regarded  as  the  unit  in  the  discussion  of  state  production, 
it  is  believed  that  owing  to  its  size,  a  somewhat  more  special  or 
minute  consideration  may  be  given  to  certain  portions  of  it.  The 
northern  half  of  the  Aroostook  Valley  is  generally  conceded  to  be 
superior  to  the  southern  half  for  the  growing  of  potatoes.  The 
heaviest  producing  section  is  that  portion  included  between  Mars 
Hill,  and  Limestone,  embracing  the  towns  of  ]\Iars  Hill,  Easton, 


Fig.  60. — Dwelling  house  and  bam  on  "Aroostook  Farm,"  Presque  Isle,  Me.  Aroo- 
stook Farm  is  a  State  Experiment  Farm  operated  by  the  Maine  State  Experiment  Station, 
Orono,  Me.  The  U.S.  Department  of  .Agriculture  carries  on  its  potato  breeding  work  on 
this  farm. 

Fort  Fairfield,  Presque  Isle,  Caribou  and  Limestone.  In  1913, 
the  Bangor  and  Aroostook  Railroad  prepared  a  sketch  map  showing 
the  distribution  of  potato  shipments  over  their  line  (Fig.  61). 
The  map  also  gives  the  number  of  miles  tributary  to  each  point, 
the  car  movement  per  mile  and  the  percentage  of  the  crop  it 
represents.  For  convenience  of  reference  the  data  are  considered 
under  ten  zone  numbers.  The  heaviest  movement  per  mile  of  road 
operated  was  that  of  zone  6  or  the  Fort  Fairfield  Branch  on  which 
260  cars  per  mile  were  moved.  The  next  highest  is  that  of  the 
Limestone  Branch,  zone  5,  with  187  cars  per  mile,  and  zone  3, 
third,  with  180  cars  per  mile. 


LONG  ISLAND,  NEW  YORK,  AND  NEW  JERSEY 


127 


The  Long  Island,  New  York  and  New  Jersey  Districts. — 

While  these  two  districts  are  not  exactly  identical  as  regards 
climate  and  soil,  the  variations  are  no  greater  than  those  found 
within  Aroostook  County.     The  planting  and  harvesting  seasons  are 


/ 


/. 


/ 


/           ^.^^^^ 

'            /<^^^l^              1  1   StockholiA  Zone3  fN\ 

''V        /                        \\     ^^^K^E^^' ALimeWtone 

r        '                    \\  Perh  A.?^  'rft^ 

\   1     20N|    V   l\^fe 

Fairfield 

Patten  «^  ^         x  '''      i       \^  \ 

SHERMANlr>'l.°^''                   I^nN 

1                          irOTACYVlLLE                     \-T 

'\ 

Zone|10 

MlLi-lNOCKET, 


LMlLLlNOCKEjI, 

W.Seboois 


Greenviuue^^       Iron^orksJ 

J^^ 

1            bROWNVlLLE^l 

\f 

y^SLDTOWN 

/N^MeJctT 

_Vbangor  /' 

ISearsport 

Fig.  61. — Sketch  map  Bangor  and   Aroostook  R.R.  showing  distribution  of  potato 
shipments.     Houlton,  Me.,  April  20,  1917. 


128 


POTATO  PRODUCTION  IN  NORTH  AND  WEST 


also  practically  identical,  thus  making  it  possible  to  consider  them 
as  one  district.  The  points  of  dilt'erences  between  the  combined 
sections  and  that  of  Maine  are  that  the  Long  Island  and  New 
Jersey  areas  have  two  distinctive  planting  seasons,  viz,  an  early 
and  a  late.  The  Irish  Cobbler  is  almost  wholly  grown  for  the  early 
crop  and  the  Green  Mountain  as  a  late,  with  the  exception  of 
Monmouth  County,  New  Jersey,  where  it  is  supplanted  by  the 
American  Giant,  which  is  an  intermediate  variety,  planted  about 


Fig.  62. — Harvesting  potatoes  on  a  Minch  Bros,  farm,  Bridgeton,  N.  J.  Potatoes  are 
gathered  in  H  bushel  baskets.    Courtesy  of  Minch  Bros.,  Bridgeton,  N.J. 

the  same  time  as  the  early  crop.  In  addition  to  these  three,  a  red 
skinned  variety  belonging  to  the  Eose  Group,  which  we  have  been 
unable  to  identify,  is  grown  to  some  extent  as  a  late  crop,  for 
which  purpose  it  seems  to  be  admirably  adapted. 

rrodudion  Cenires. — The  chief  ])otato-producing  centres  in 
New  Jersey  are  located  in  Monmouth,  Salem,  Mercer,  Middlesex 
and  Cumberland  Counties.  The  chief  shipping  ])oints  are  Free- 
hold, Howell,  ]\Iarlboro,  Tennent  and  Englishtown  in  IMonmouth; 
Salem,  Woodstown,  Elmer  and  Daretown  in  Salem:  Hightstowm, 
Eobbinsville,  Yardville  and  Windsor  in  Mercer;  Cranbury  and 
Prospect  Plains  in  Middlesex;  and  Bridgeton  and  Tlusted  in 
Cumberland  Countv. 


LONG  ISLAND,  NEW  YORK,  AND  NEW  JERSEY 


129 


The  Long  Island  district  is  represented  by  Suffolk  County,  in 
which  the  leading  ship])iug  points  are  Riverhead,  Aquebogue, 
Cutchogue,  Bridgehampton,  Southold,  Mattituck  and  Orient. 

Soil  and  Climatic  Conditions. — The  soil  in  the  more  intensive 
potato-])roducing  areas  on  Long  Island  and  in  New  Jersey  is  of  a 
more  or  less  sandy  nature,  and  could  be  designated  as  belonging  to 
the  Norfolk  series,  being  a  continuation  of  the  same  general  type 
of  soil  as  that  of  the  Eastern  Shore  of  Maryland  and   A^irginia. 

The  climate  of  Long  Island  is  very  much  modified  by  the  ocean 


•^*'v 


'^ 


of  basket'5      Courteby  ol  Ml 


bridgLton,  \    J 


irmit  of  hauling  a  large  number 


on  the  south  and  east  and  the  Sound  on  the  north ;  this  imparts 
to  the  surrounding  territory  a  milder  and  more  equable  climate 
than  that  which  prevails  in  the  same  latitude  further  inland.  The 
climate  of  New  Jersey,  especially  that  of  the  southern  half  of  the 
state,  is  not  as  well  suited  to  the  potato  as  is  that  of  Long  Island, 
l)ecause  it  is  generally  warmer  and  drier.  In  New  Jersey,  the 
practice  of  planting  second  crop  home  grown  seed  is  on  the  increase, 
l)ut  the  bulk  of  the  seed  is  procured  in  the  North. 

Source  of  Seed. — The  Long  Island  grower  is  almost  wholly 
dependent  upon  northern  grown  seed.  Maine,  Vermont  and 
northern  New  York  growers  supply  the  bulk  of  the  seed  used. 
Some  New  Jersey  second  crop  seed  is  planted,  but,  as  yet,  the 
amount  used  is  rather  negligible. 

During  the  past  year,  (1920),  Wisconsin  Green  Mountains, 
9 


130  POTATO  PRODUCTION  IN  NORTH  AND  WEST 

aiid  Prince  Edward  Island  American  Giants  have  been  planted 
to  some  extent. 

Cultural  Practices. — In  general,  the  same  cultural  methods  are 
pursued  as  in  Maine,  with  this  exception,  that  both  the  level  and 
modified  ridge  culture  is  practised.  The  distance  and  rate  of 
planting  is  very  much  the  same,  as  is  also  the  use  of  commercial 
fertilizers,  with  the  possible  exception  that  they  are  not  used 
quite  as  prodigally  as  in  Maine.  As  a  rule,  the  fertilizer  applied 
to  the  early  crop  contains  a  higher  percentage  of  available  nitrogen 
than  is  used  by  the  Maine  grower,  this  being  done  for  the  purpose 
of  hastening  the  development  of  the  plants.  Few  growers  in  either 
of  these  sections  practise  spraying  as  thoroughly  as  in  Aroostook 
County.  This  is  partly  due  to  the  absence  of  late  blight  in  so  many 
of  the  seasons  that  the  grower  becomes  careless  and  is  willing  to 
take  a  chance,  with  the  result  that  every  few  years  his  crop  is 
severely  attacked  with  the  disease,  and  heavy  losses  through  tuber 
decay  are  incurred.  This  was  the  case  in  some  counties  of  New 
Jersey  in  1919,  Avhen  a  severe  attack  of  late  blight  caused  con- 
siderable loss. 

Harvesting  the  Crop. — l^he  southern  half  of  New  Jersey  har- 
vests its  potato  crop  somewhat  in  advance  of  the  northern  half  of 
the  state,  as  well  as  of  Long  Island.  The  crop  movement  from 
New  Jersey  in  1916,  as  indicated  by  percentage  of  crop  harvested, 
shows  that  3  per  cent  was  dug  in  June,  18  in  July,  36  in  August, 
26  in  September,  and  18  in  October.^  This  data  affords  a  fair  index 
to  the  proportion  of  the  crop  that  is  grown  for  early  and  late  mar- 
keting; it  is  not  necessarily  an  accurate  one  because,  in  either  of 
the  two  districts  under  consideration,  the  harvesting  of  the  early 
crop  is  materially  hastened  or  delayed,  according  to  whether  prices 
are  high  or  low  during  the  normal  period  in  which  it  should  be  dug. 
A  considerable  portion  of  the  New  Jersey  crop  is  handled  in  five- 
eighth  l)usliel  baskets  (Figs.  62  and  63). 

New  England  and  Northern  New  York. — The  New  England 
States,  exclusive  of  Maine,  and  northern  Nev/  York  are  sufficiently 
identical  in  climatic  conditions,  cultural  practices,  and  varieties 
grown  to  be  considered  as  one  general  area.  With  few  exceptions, 
potatoes  are  not  groAvn  in  this  region  as  an  early  crop.  Outside 
of  northern  New  York  and  certain  towns  in  Vermont,  very  little 
seed  stock  is  grown  other  than  for  local  use.  The  Irish  Cobbler 
is  the  leading  early  variety,  and  the  Green  Mountain  the  leading 


WESTERN  NEW  YORK  AND  PENNSYLVANIA  131 

late  one.  The  crop  is  usually  planted  during  May  and  the  first 
week  in  June;  though  in  the  more  favored  sections  of  Connecticut, 
Khode  Island,  and  Massachusetts,,  the  crop  is  often  planted  in  April, 
especially  early  varieties  such  as  the  Irish  Cobbler,  Quick  Lunch, 
and  others.  Few  large  growers  are  found  in  this  area,  the  average 
acreage  of  commercial  growers  ranging  from  3  to  20  acres,  with 
an  occasional  grower  considerably  exceeding  this  amount. 

Western  New  York  and  Pennsylvania. — The  general  potato- 
producing  sections  of  western  New 
York  and  Pennsylvania  are  very  much 
alike,  insofar  as  varieties  grown  are 
concerned.  Most  of  the  potato  crop 
produced  in  this  region,  outside  of 
areas  adjacent  to  the  larger  cities,  con- 
sists of  late  varieties  intended  for  fall 
and  winter  consumption.  A  compari- 
son of  the  production  of  these  two 
states  during  the  years  1910-1919, 
inclusive,  shows  a  variation  in  New 
York  State  from  a  trifle  over  22 
million  bushels  in  1915  to  nearly  53.25 
million  bushels  in  1914,  with  a  varia-        ,^     ^,     t^    .  ,  t^      ,.t-  u  i 

'  Fig.  64. — Daniel  Dean,  Nichols, 

tion   in  acreage  of  only  a  trifle  over  n.y.  a  noted  authority  on  potato 

J^  •'  .       .  culture  who  has  been  highly  success- 

3  per  cent.     The  range  of  variation  m  fui  in  the  production  of  large  crops 

_  ,  .  »  T,,i  w-  of  high  quality  potatoes.     Mr.  Dean 

Pennsylvania  was   from  a  little  over    15  makes  a  speciality  of  the  Rural  New 

■  -.■,.         -,        ,     ,      .       ^rv^^x      c\r\  r'         ^^1^  Yorker  Variety.  He  is  also  well  known 

million  bushels   m   1911   to  29.5   million  as  a  writer  and  platform  speaker.    His 

irnrv         'i.!,  •  •       i>  practical    experience    coupled    with 

m   1917,   With  an   acre   increase  m  lavor  keen  powers  of  observation  and  an 

of  the  latter  period  of  about  16  per  S  ma^Yim 'l^Tr^ifuf  wrto 
cent.  The  varieties  most  commonly  ^^^d  lecturer, 
grown  are  chiefly  members  of  the  Green  Mountain  and  Eural 
groups.  The  Eural  varieties  are  more  generally  grown  as  they  have 
proven  to  be  better  adapted  to  the  climatic  conditions  of  western 
New  York  and  certain  sections  of  Pennsylvania  than  the  Green 
Mountain  class.  In  Washington  County,  New  York,  the  American 
Giant  is  rather  extensively  grown  for  the  New  Jersey  seed  trade. 
The  Irish  Cobbler  and  the  Early  Ohio  are  the  leading  early  varieties. 
Cultural  Practices. — Cultural  practices  vary  in  different  locali- 
ties. In  some  sections  the  planting  of  the  late  crop  is  delayed 
until  the  latter  part  of  May  or  forepart  of  June ;  this  is  particularly 


132  POTATO  PRODUCTION  IN  NORTH  AND  WEST 

true  ill  western  Now  York,  wliile  in  other  sections,  the  cro])  is 
planted  the  latter  part  of  April  or  early  in  May,  The  date  of 
planting  is  governed,  to  a  large  extent,  by  the  normal  weather 
conditions  prevailing  in  any  given  locality  at  the  time  the  plants 
are  developing  their  tubers.  Roberts  and  Clijiton  ^  say :  "  Early 
])lanting  of  potatoes  and  frequent  tillage  to  conserve  moisture  M'ill 
ordinarily  give  best  results." 

The  New  York  growers,  as  a  rule,  plant  larger  acreages  than 
do  New  England  or  Pennsylvania  growers.  Modern  potato  imple- 
ments are  very  generally  employed  in  the  jdanting,  care,  and 
harvesting  of  the  crop.  The  ridge  or  hilling  system  of  culture  is 
quite  generally  practised  throughout  New  York  State.  There  are 
those,  of  course,  who  prefer  level  culture  but  they  are  in  the  mi- 
nority. In  Pennsylvania,  both  systems  are  in  vogue.  Investiga- 
tions reported  by  Stone,*^  in  1905,  would  seem  to  indicate  that 
level  culture,  at  least  in  the  vicinity  of  Itliaca,  was  preferable  to 
hilling.  The  following  data  covering  three  seasons  are  taken 
from  Stone's  report : 

hilled,  yielded  at  the  rate  of  288  bushels  per  acre, 
1897—     J 

level,    yielded  at  the  rate  of  384  bushels  per  acre,  96  bu.  increase. 


1898- 


1899- 


hilled,  yielded  at  the  rate  of  327  bushels  per  acre, 

level,    yielded  at  the  rate  of  345  bushels  per  acre,  18  bu.  increase. 

hilled,  yielded  at  the  rate  of  194  bushels  per  acre, 

level,    yielded  at  the  rate  of  241  bushels  per  acre,  47  bu.  increase. 


Spraying  is  no  more  general  or  thorougli  in  these  two  states 
than  in  New  I^ngland.  There  are,  however,  some  very  worthy 
exceptions.  Two  of  the  most  striking  that  have  attracted  my  at- 
tention are  those  of  Daniel  Dean  of  Nicliols,  N.  Y.,  (Fig.  64) 
and  T.  E.  Martin  of  West  Rush,  N.  Y.  These  gentlemen  are  firm 
l)elievers  in  thorough  spraying.  They  are  not  satisfied  to  call  their 
job  done  when  they  have  sprayed  their  potato  fields,  four,  six,  or 
even  eight  times,  but  have  been  known  to  spray  as  often  as  sixteen 


WESTERN  NEW  YORK  AND  PENNSYLVANIA 


133 


times  (luring  the  season.  The  increased  yields  t]ie.y  secure  are,  in 
their  Judgment,  ample  justification  for  the  extra  spray  material  and 
the  labor  involved  in  making  so  many  applications.  In  all  of  the 
strictly  commercial  sections  the  crop  is  harvested  with  the  elevator 
type  of  potato  digger.  ]\Iost  of  the  New  York  State  growers  use 
bushel  crates  in  which  to  ])ick  up  and  haul  the  potatoes  to  the 
storage  house  or  cellar   (Fig.  65).     As  a  rule,  neither  New  York 


Fig.  65. — Harvesting  Sir  Walter  Raleigh  potatoes,  T.  E.  Martin's  farm  West  Rush, 
N.Y.     The  potatoes  are  picked  up  in  bushel  crates.     Courtesy  of  T.  E.  Martin. 

or  Pennsylvania  growers  have  made  as  ample  provision  for  the 
storage  of  the  potato  crop  as  have  either  the  Maine  growers  or 
those  in  the  "far-west"  states  such  as,  Colorado,  Utah,  and  Idaho. 
The  house  or  barn  cellar  rather  than  the  special  potato  storage 
house  is  utilized  quite  generally  throughout  both  states 
under  consideration. 

The  per  acre  yield  in  both  New  York  and  Pennsylvania  is  far 
l)elow  what  it  should  be,  and  what  it  must  be  in  the  near  future, 
when  greater  demands  will  be  made  upon  all  tillable  lands  to 
produce  larger  supplies  of  food.  The  average  per  acre  production 
of  New  Y'ork  for  the  years  1915  to  1919  is  only  87.1  bushels; 
and  that  for  Pennsylvania  is  still  less,  82.8  bushels.  When  it 
is  remembered  that  Long  Island  and  northern  New  York,  where 
larger  yields  are  secured,  are  included  in  this  average,  it  is  evident 


134 


POTATO  PRODUCTION  IN  NORTH  AND  WEST 


that  the  average  yield  in  western  New  York  is  considerably  less 
than  the  figure  mentioned.  That  yields  very  largely  in  excess  of 
these  may  be  grown,  when  proper  cultural  care  is  given  to  the  crop, 
have  been  amply  proven  by  Roberts  and  Clinton,^  in  their  four 
reports  on  potato  culture.  From  these  four  publications  the  fol- 
lowing data  on  yields  secured  on  the  Station  farm  are  presented: 

1895 — 352.6  bushels 
1896—333.0  bushels 
1897—322  0  bushels 
1898—278.0  bushels 
1899—202.0  bushels 
1900—200  0  bushels 

These  data  are  significant  in  that  they  furnish  conclusive  evi- 
dence of  the  feasibility  of  very  materially  increasing  the  per  acre 
yield  of  potatoes,  not  only  in  New  York  State,  but  in  every  other 
state  where  climate  and  soil  are  favorable  to  the  growth  of  the 
potato  plant. 

Ohio,  Indiana,  Illinois,  Iowa,  and  Missouri. — These  five  states 
represent  the  central  portion  of  the  geographical  area  included  in 
the  Bureau  of  Crop  Estimates  division  known  as  the  North  and 

Average  Acreage  Production  and  Yield  Per  Acre  and  Principal  Varieties 
Groicn— 1915-1919. 


State 

Rank 
in  pro- 
duction 

Acreage 

Yield 

in 
bushels 

Bushels 
per 
acre 

Principal  varieties  grown 

Ohio.... 
Illinois. . 
Iowa 

Missouri 
Indiana. 

8 

10 
11 

10 
19 

152,600 
137,000 
130,800 

98,200 
82,600 

12,027,200 
10,715,800 
10,566,000 

6,926,400 
6,521,000 

78.2 
78.0 
80.0 

70.2 

78.2 

Early  Ohio,  Green  Mountain,  Rural 
Early  Ohio,  Early  Michigan,  Rural 
Rural,  Green  Mountain,  Early  Ohio,  Bur- 
bank.  Irish  Cobbler 
Early  Ohio 
Rural,  Green  Mountain,  Early  Ohio, 

Irish  Cobbler 

West.  While  none  of  the  five  are  large  producers  of  potatoes,  as 
compared  with  the  six  leading  states  of  this  division,  they  never- 
theless are,  as  will  be  noted  in  the  above  table,  well  up  in  the 
list,  ranking  between  eight  and  nineteen,  inclusive.  A  study  of  the 
yield  per  acre  column  shows  that  three  of  the  five  states  are  iden- 
tical, 78.2  bushels,  while  the  Iowa  average  is  80  bushels  and  Mis- 
souri only  70.2.  It  is  evident,  therefore,  that  the  general  climatic 
and  soil  conditions  must  be  more  or  less  similar. 


OHIO,  INDIANA,  ILLINOIS,  IOWA,  AND  MISSOURI         135 

Production  Centres. — The  chief  producing  centres  in  Ohio  are, 
according  to  Ballon,-  the  counties  of  Portage,  Wayne,  Medina, 
Cuyahoga,  Hamilton,  Stark,  Lucas,  Summit,  Erie,  and  Mahoning. 
He  further  states  that,  if  the  state  be  roughly  divided  into  four 
quarters,  it  would  be  found  that  the  northeastern  quarter  produced 
over  one  half  the  total  crop  of  the  state.  In  Illinois,  the 
chief  centres  are  located  in  Cook,  Saint  Clair,  Madison,  Whiteside, 
and  Winnebago  Counties.  In  Iowa,  the  leading  counties  are  Grundy, 
Scott,  Tama,  Marshall,  Mitchell  and  Pottawattamie.  The  Missouri 
centres  of  production,  so  far  as  counties  are  concerned,  are  St.  Louis, 
Bay,  Buchanan,  Jackson,  and  Andrew,  Those  of  Indiana  are  La 
Porte,  St.  Joseph,  Allen,  and  Elkhart. 

Cultural  Practices. — Relatively  little  commercial  fertilizer  is 
used  in  the  production  of  potatoes  throughout  these  five  states. 
In  northern  Ohio,  according  to  Green,^  the  first  two  weeks  in  May 
is  considered  the  most  suitable  time  to  plant.  In  northern  Indiana, 
Illinois,  and  Iowa,  the  planting  date  for  the  late  crop  is  similar 
to  that  of  Ohio.  Potatoes  intended  for  early  market  might  be 
planted  considerably  earlier.  The  planting  date  in  the  southern 
portion  of  these  three  states  is  at  least  three  weeks  earlier.  In 
Missouri,  the  planting  date  in  the  northern  portion  is  similar  to 
that  of  the  southern  part  of  the  preceding  states,  while  in  the 
southern  portion,  the  planting  date  is  advanced  to  March.  In  fact, 
in  some  localities,  Essex,  for  example,  the  growing  season  is  suffi- 
ciently long  to  permit  of  growing  a  second  crop.  In  such  c;ases, 
the  early  crop  may  be  planted  the  latter  part  of  February. 

Modern  machinery  is  generally  used  in  planting,  cultivating, 
and  harvesting  the  crop.  Level  culture,  rather  than  ridging,  is 
almost  universal.  Spraying,  except  for  insect  pests,  is  not  a 
general  practice. 

Marl'ets. — With  the  exception  of  Ohio  and  Iowa  in  years  of 
high  production  none  of  these  states  produce  enough  potatoes  for 
home  consumption;  their  markets  are  local  rather  than  foreign,  as 
the  crop  is,  theoretically  at  least,  entirely  consumed  within  their 
own  boundaries.  It  is  quite  probable  that  this  group  of  states 
will  continue  to  depend  upon  outside  sources  for  a  portion  of  their 
table  stock  supply.  At  present,  they  are  dependent  upon  outside 
sources,  largely  Michigan,  Wisconsin,  and  Minnesota,  for  a  portion 
of  their  seed  stock,  and  the  probability  is  that  still  greater  depen- 
dence will  be  placed  upon  these  states. 


136  POTATO  PRODUCTION  IN  NORTH  AND  WEST 

Michigan.  Wisconsin,  and  Minnesota. — This  trio  of  states 
possess  approximately  the  same  climatic  and  soil  conditions.  They 
are  large  potato  producers  and  are  capable  of  very  materially  in- 
creasing their  output  whenever  there  is  a  market  for  it.  In  total 
production,  Michigan,  Wisconsin,  and  Minnesota  rank  second,  third, 
and  fourth.  Sometimes  one  or  other  of  them  forces  New  York  to 
take  second  place.  The  only  widely  known  potato  territory  in  this 
group  of  states  is  that  of  the  Red  Eiver  Valley  in  Minnesota. 
Other  large  shipping  sections  aside  from  the  lied  Eiver  Valley  in 
Minnesota  are  Elk  Eiver,  Princeton,  Anoka,  etc.  In  Wisconsin, 
the  central  portion  of  the  state  including  Waupaca,  Portage,  and 
Waushara  Counties,  represented  the  largest  producing  centres  in 
1909,  but  for  the  next  ten  years  or  more,  the  commercial  potato 
belt  has  been  constantly  moving  northward,  keeping  pace  as  it 
were,  with  the  subjugation  of  the  cutover  timber  lands  in  not  only 
Wisconsin  hut  the  other  two  states  as  Avell.  A  large  portion  of 
this  type  of  land  seems  to  be  admirably  adapted  to  clover  and  pota- 
toes. In  fact,  clovers  grow  so  naturally  and  luxuriantly  throughout 
most  of  this  section  that  it  has  been  very  happily  designated 
"Cloverland."  The  commercial  potato  development  of  the  future, 
in  the  "Middle  West,"  is  almost  certain  to  be  very  largely  centred 
in  "Cloverland."     Michigan  has  no  outstanding  potato  district. 

Extent  of  the  Crop. — The  production  of  these  three  states  can 
be  more  easily  comprehended  from  the  data  presented  in  the 
table  which  gives  the  annual  yields  for  the  ten  years,  1910  to 
1919  inclusive. 

A  comparison  of  these  data  show  that  Michigan's  average  i)ro- 
duction  for  the  ten-year  period  is  a  trifle  over  31  million  bushels, 
Wisconsin  29.8,  and  Minnesota  nearly  27  million  bushels.  The 
most  interesting  feature  of  these  data  is  that  of  the  wide  fluctua- 
tions in  yield  from  year  to  year  with  a  relatively  small  fluctuation 
in  acreage.  In  Michigan,  extremely  low  yields  prevailed  during 
the  years  1915  and  1916.  Wisconsin's  low  mark  came  in  1916, 
while  Minnesota  shows  low  yields  in  191 0  and  1916.  These  low 
yields  were  due  to  unfavorable  climatic  conditions. 

Varieties  Grown. — The  varieties  grown  in  this  area  are  mainly 
the  Irish  Cobbler,  Early  Ohio,  and  Triumph,  for  early  varieties, 
and  the  Green  Mountain,  Eural,  and  Eusset  Eural,  for  late.  Other 
varieties,  grown  to  a  lesser  extent  are  the  Pearl,  King,  Burbank, 


MICHIGAN,  WISCONSIN,  AND  MINNESOTA 


137 


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CO 

35.175,000 
31,020,000 
36,750,000 
33,600,000 
44,044,000 
20,945,000 
15,360,000 
35,910,000 
28,560,000 
28,688,000 

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138  POTATO  PRODUCTION  IN  NORTH  AND  WEST 

and  Eusset  Burbank.  The  Early  Ohio  is  the  most  extensively 
gro^\ai  early  variety  in  Minnesota.  In  Wisconsin,  a  strong  effort 
is  being  made  to  develop  a  large  Triumph  seed  trade  in  the  South 
and,  as  a  natural  result,  Triumph  acreage  is  on  the  increase. 
Michigan  has  no  very  well  developed  seed  trade,  and  is  not  exten- 
sively engaged  in  the  production  of  early  potatoes,  except  to  supply 
local  markets. 

Cultural  Practices. — The  cultural  practices  in  vogue  in  Michi- 
gan, Wisconsin,  and  Minnesota  do  not  differ  essentially  from  the 
central  group  of  states  with  respect  to  planting  and  tillage  of  the 
crop.  Level  culture  is  practised.  As  a  rule,  most  growers  use  too 
small  an  amount  of  seed,  10  to  12  bushels,  rather  than  15  to  18. 
In  some  sections  of  these  states,  one  still  finds  growers  using  the 
hill  instead  of  drill  method  of  planting  potatoes.  The  rows  are 
usually  spaced  36  inches  apart  and  the  plants  in  the  row  from  24 
to  36  inches  apart,  mostly  30  to  36  inches  apart,  the  field  being 
marked  in  both  directions  with  a  marker,  after  which  it  is  planted 
with  hand  planters.  The  hill  method  of  culture  is  usually  found 
on  the  cheaper  and  less  productive  lands,  and  is  largely  practised 
in  order  to  permit  of  cultivating  the  crop  in  both  directions  with 
horse  implements,  thereby  doing  away  with  hand  labor. 

North  and  South  Dakota,  Nebraska,  and  Kansas. — These 
four  states  are  the  western  tier  of  the  North  and  West  division  of 
21  states.  They  are,  in  reality,  the  western  states  of  this  division. 
In  point  of  production  with  other  states,  they  rank  as  follows: 
Nebraska  13;  North  Dakota  17;  South  Dakota  18;  Kansas  25. 
Eelatively  speaking  they  are  not  large  producers,  though  as  a  rule, 
except  possibly  in  Kansas,  they  produce  more  than  enough  for 
their  own  needs.  The  production  by  years  from  1910  to  1919,  as 
given  in  the  table  of  this  group,  shows  a  very  low  average  yield 
in  Kansas  as  compared  with  the  other  states.  Kansas  also  shows 
the  widest  percentage  range  between  the  highest  and  loAvest  acre 
yields.  These  four  states  are  of  interest,  aside  from  their  consti- 
tuting the  western  tier  of  states  of  the  North  and  West  division,  in 
that  certain  sections  of  all  of  them  can  be  irrigated.  Irrigation 
plays  a  more  important  role  in  commercial  potato  production  in 
northwestern  Nebraska  and  southwestern  South  Dakota  than 
in  North  Dakota  and  Kansas. 

Potato  Production  Centres. — The  chief  production  districts  in 


NEBRASKA,  KANSAS  AND  THE  DAKOTAS 


139 


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140 


POTATO  PRODl'CTION  IN  NORTH  AND  WEST 


Xpl)raska  are  in  Uw  northwestern  section,  Tlie  leading  counties 
are  Hcottsblutl',  Sheridan,  Box  Butte,  Douglas,  and  Sioux.  During 
the  past  two  years,  the  Kearney  district  has  come  into  considerable 
prominence  as  an  early  market  production  centre.  South  Dakota 
has  no  well  defined  area.  The  leading  counties  are  Brown,  Minne- 
haha, Spink,  Brookings,  and  Day.  The  IJed  Eiver  Valley  district 
on  the  eastern  border  of  Xorth  Dakota,  with  Grand  Forks  and 
Larimore  as  the  centre,  is  the  chief  commercial  potato  production 
centre  of  that  state.  The  chief  producing  centre  in  Kansas  is  the 
Kansas  or  Kaw  Eiver  Valley  extending  from  Kansas  City  to 
Topeka.  The  leading  counties  are  Wyandotte,  Johnson,  Leaven- 
worth, Douglas,  and  Jefferson. 

Varieties  Grown. — The  varieties  grown  in  a  commercial  way 
are  quite  similar  to  those  grown  in  tlic  states  to  tlie  East.  They 
are  as  follows : 


North   Dakota 


Early  Ohio 

Irish  Cobbler 

Triumph 

Rural 

Green  Mountain 


South  Dakota 


Early  Ohio 
Irish  Cobbler 
Triumph 
Rural 


Nehi'aska 


Early  Ohio 

Triumph 

Pearl 

Rural 

Russet  Rural 

Charles  Downinji 


Kansas 


Early  Ohio 
Irish  Cobbler 
Triumph 
Ciolcl  Coin 


The  Early  Ohio  is  the  leading  variety  in  the  eastern  ])ortion 
of  these  four  states.  The  Triumph  is  of  greatest  importance  in 
northwestern  Nebraska,  where  i!:  is  being  grown  rather  extensively 
for  seed  purposes  on  both  dry  and  irrigated  land,  largely  the  former. 
This  seed  stock  finds  a  ready  market  in  Louisiana,  Texas,  Okla- 
homa, Arkansas,  and  other  southern  points. 

Cultural  Practices. — Where  irrigation  is  not  practised,  level 
cultivation  with  a  slight  ridging  with  last  cultivation  is  the  usual 
method.  When  grown  under  irrigation,  the  ridge  culture  method 
becomes  a  necessity  because  -it  provides  the  only  feasible  way  of 
irrigating  the  crop.  The  usual  distance  between  the  rows  is  three 
feet,  but  in  some  sections  a  wider  spacing  is  allowed,  this  being 
particularly  true  under  dry  land  culture.  Owing  to  the  almost  if 
not  complete  absence  of  the  late  blight  fungus  in  this  region,  few, 
if  any,  growers  practise  spraying  their  crop,  except  with  arsenical 
poisons,  as  a  protection  against  insect  pests.  The  crop,  as  a  whole, 
is   largely  grown   for  table   stock,   intended   for   fall   and   winter 


THE  FAR-WESTERN  STATES  141 

consumption  and  for  seed  purposes,  rather  than  for  the  early 
market.  The  Early  Ohio  of  the  Eed  River  Valley  is  marketed 
for  seed  purjjoses  in  eastern  Nehraska,  Kansas,  and  points  East. 

The  Far-Western  States. — The  eleven  states  included  in  the 
geographical  division  known  as  the  Far- Western  States  are  Wy- 
oming, Colorado,  Xew  Mexico,  Arizona,  Nevada,  Utah,  Montana, 
Idaho,  Oregon,  Washington,  and  California.  Of  these,  California, 
Colorado  and  Washington  are  the  largest  producers;  Arizona  and 
New  Mexico  the  smallest.  Colorado  has  the  distinction  of  being 
the  heaviest  shipj^er  of  potatoes  to  markets  outside  of  her  own 
borders.  In  all  of  these  states,  potatoes  are  grown  both  under 
irrigation  and  dry  land  conditions.  In  the  Pacific  Coast  states, 
l^articularly  Washington  and  Oregon,  the  climatic  condition,  so 
far  as  precipitation  is  concerned,  is  very  similar  to  that  in  the 
Jiortheastern  United  States. 

The  data  presented  in  the  table  of  this  group  show  the  average 
acreage  yield  in  bushels,  and  bushels  per  acre  of  each  of  the  far- 
western  states  for  the  years  1910  to  1914,  1915  to  1919,  and  1910 
to  1919.  This  summary  shows  that  California  leads  in  production 
in  both  five-year  periods,  but  does  not  lead  in  bushels  per  acre. 
Nevada  ranks  first  in  yield  per  acre,  Avith  Utah  and  Idaho  close 
rivals  for  second  place.  Too  great  importance  should  not,  however, 
be  attached  to  the  relative  yields  per  acre  in  the  various  states, 
as  this  is  very  largely  influenced  by  the  per  cent  of  the  acreage  that 
is  under  irrigation.  Take  Colorado,  for  exami)le,  where  quite  a 
large  acreage  is  grown  under  dry  land  conditions,  the  yields  may 
vary  from  50  to  150  bushels  per  acre.  The  same  seed  stock,  under 
average  conditions,  would  produce  from  300  to  400  bushels  on 
irrigated  land.  In  fact,  yields  of  over  500  bushels  per  acre  have 
l)een  frequently  obtained  on  rather  large  acreages,  both  in  Colorado 
and  elsewhere.  It  is  necessary,  therefore,  to  remember,  when  com- 
paring yields  from  one  state  with  those  from  another,  that  the  only 
true  basis  of  study  is  that  of  comparing  the  irrigated  sections. 
In  the  absence  of  complete  data,  regarding  the  actual  acreage  in 
each  of  the  far-western  states  of  irrigated  and  non-irrigated  pota- 
toes, it  is  not  possible  to  make  such  comparison. 

Varieties  Grown. — While  the  list  of  varieties  grown  in  these 
states  is  somewhat  larger  than  is  now  regarded  as  good  commercial 
practice,  the  actual  number  grown  in  any  given  section  is  not  really 
a  large  one. 


142 


POTATO  PRODUCTION  IN  NORTH  AND  WEST 


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60,600 
52,700 
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39,400 
18,900 
18,700 
10,400 
8,700 
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10,652,400 
8,593.000 
8,441,300 
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2,302,200 
1,778,100 
769,200 
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86.4 

THE  FAR-WESTERN  STATES  143 

The  accompanying  list  of  .varieties,  submitted  for  each  state, 
is  believed  to  include  most  of  those  that  are  more  generally 
grown  commercially : 

Arizona. — Triumph. 

California. — Burbank,  Russet  Burbank,  White  Rose,  Chas.  Downing 
(Idaho  Rural),  Early  Rose. 

Colorado. — Pearl,  Rural.  Russet  Burbank.  Brown  Beauty,  Chas.  Downing, 
Perfect  Peachblow    (Red  McClure),  Early  Ohio,  Irish  Cobbler. 

Idaho.— Cha.s.  Downing,   Rural,   Russet  Burbank,   Early  Ohio. 

Montana. — Rural,  Green  Mountain,  Russet  Burbank,  Pearl,  Irish 
Cobbler,  Triumph,  Early  Rose,  Early  Ohio. 

Nevada. — Rural,  Burbank,  Russet  Burbank,  Pearl  ( Peerless ) ,  Perfect 
Peachblow,   Early   Ohio. 

Neic  Mexico. — Irish  Cobbler. 

Oregon. — Burbank,  Pride  of  Multnomah,  Russet  Burbank,  White  Rose, 
Early  Ohio. 

Utah. — Chas.    Downing,   Rural,    Russet    Burbank. 

Washingto7i. — Burbank,  Russet  Burbank,  Chas.  Downing,  Rural,  Early 
Ohio. 

Wyoming. — Pearl,   Chas.   Downing,  Russet  Burbank,  King. 

Produciion  Centres. — Generally  speaking,  the  west  and  far- 
western  states  have  more  clearly  defined  production  centres  than 
in  the  East.  This  is  due  to  the  fact  that  a  large  per  cent  of  the  crop 
is  grown  under  irrigation  and  is  therefore  confined  to  these  areas. 

Colorado. — In  Colorado,  the  potato  industry  is  roughly  segre- 
gated into  seven  districts  known  as  the  Greeley,  Divide,  North- 
western, Intermountain,  Western  Slope,  Southwestern,  and  the 
San  Ijuis  Valley.  The  Greeley  district,  located  in  Weld  County, 
is  so  well  known  that  little  need  be  said  regarding  it.  Until  the 
year  1909,  it  had  always  enjoyed  the  distinction  of  being  the 
largest  production  centre  in  the  state,  and  prior  to  1910  was  con- 
sidered the  second  largest  potato-producing  section  in  the  United 
States.  In  1909,  10,000  carloads  of  potatoes  were  shipped  out  of 
the  county;  and  the  1910  census  report,  based  on  the  1909  crop, 
credits  Weld  County  with  a  production  of  5,857,691  bushels,  an 
amount  in  excess  of  the  total  production  of  seven  of  the  eleven 
states  included  in  the  far-western  group.  Unfavorable  weather 
conditions,  accompanied  by  a  severe  epidemic  of  potato  diseases 
during  the  years  1910  to  1914,  very  nearly  wiped  out  the  industry 
commercially.  Since  1914,  there  has  been  a  gradual  improvement 
in  conditions,  and  the  district  is  rapidly  coming  back  into  its  own 
as  a  commercial  potato-producing  centre. 

The  Divide  district  includes  portions  of  three  counties,  Douglas, 


POTATO  PRODUCTION  IN  NORTH  AND  WEST 


COLORADO  145 

l^^lbert,  and  El  Paso.  It  occupies  the  elevated  central  section  of 
the  "Eastern  Slope"  of  the  Eockies.  The  rainfall  of  this  district, 
particularly  of  the  more  elevated  portions  which  reach  an  altitude 
of  7,500  feet,  is  sufficiently  heavy,  nearly  20  inches,  to  permit  of 
growing  a  crop  of  potatoes  without  irrigation.  This  is  made  pos- 
sible by  a  cool  summer  climate,  which  furnishes  ideal  conditions 
for  the  production  of  good  seed  potatoes.  About  3,000  acres  of 
potatoes  are  grown  in  the  district. 

The  Nortliivesiern  district  is  of  relatively  little  importance 
commercially.  It  includes  portions  of  Moffat  and  Eoutt  Counties, 
located  in  the  extreme  northwestern  part  of  the  state.  The  cli- 
matic conditions  are  very  similar  to  those  of  the  Divide  section. 
The  Early  Ohio  and  the  Eusset  Burbank  are  the  leading  varieties. 
The  area  devoted  to  potatoes  is  about  750  acres. 

The  Intermountain  disirid  is  generally  referred  to  as  the 
C'arbondale  district,  but  this  is  somewhat  erroneous,  as  it  also  in- 
cludes the  Eagle  Eiver  district.  These  are  located  in  Garfield  and 
Eagle  Counties,  respectively.  Owing  to  the  relatively  high  altitude 
of  the  intermountain  district,  6,000  feet  and  above,  the  climatic 
conditions  are  very  favoralile  to  potato  production.  Both  the  Eagle 
and  Carbondale  districts  have  an  abundant  supply  of  irrigation 
water  drawn  from  the  Eagle  and  Crystal  Elvers.  The  leading 
varieties  are  the  Eusset  Burbank  (Fig.  QQ>),  Peachblow  (Fig.  67), 
Eural,  and  Charles  Downing.  The  total  area  devoted  to  the  potato 
is  about  5,500  acres.  The  Crystal  Eiver  Land  Company,  generally 
referred  to  as  the  Sweet  Eanch,  has  long  enjoyed  an  enviable  repu- 
tation in  the  production  of  large  per  acre  yields.  The  present  and 
former  associate  proprietors  are  shown  in  figures  68  and  69. 

The  Western  Slope  district  embraces  the  valleys  of  the  Grand, 
Gunnison,  and  Uncompagre  Eivers,  and  the  adjacent  irrigated 
mesas.  Portions  of  Mesa,  Delta,  and  Montrose  Counties  are  in- 
cluded in  this  district.  The  leading  varieties  are  Irish  Cobbler, 
Charles  Downing,  People's,  Eusset  Burbank,  and  Eural.  Over 
6,000  acres  of  potatoes  are  grown  in  this  territory. 

The  Southwestern  district  consists  of  the  irrigated  valleys  and 
mesas  of  Montezuma  and  La  Plata  Counties.  The  comparative 
unimportance  of  the  potato  industry  of  this  section  is  largely  due 
to  poor  shipping  facilities.  The  soil  and  climate  is  well  suited 
to  potato  production.  The  leading  varieties  are  Early  Ohio,  Eus- 
set Burbank,  and  Eural.     Acreage  2,000. 


14G  POTATO  PRODUCTION  IN  NORTH  AND  WEST 


WYOMING 


147 


The  San  Luis  Valley  district  enjoys  the  distinction  of  having 
produced  a  larger  crop  of  potatoes  in  1919  than  the  Greely  district, 
and  there  is  a  possibility  of  its  ultimately  becoming  the  leading 
production  centre  in  the  state.  This  elevated  plain,  with  altitude 
at  some  points  exceeding  7,500  feet,  is  located  in  the  south  central 
portion  of  the  state.  The  larger  portion  of  the  potato-producing 
section  is  in  Rio  Grande  County.  Most  of  the  area  is  irrigated. 
The  leading  varieties  are  Brown  Beauty,  Eusset  Burbank,  Early 
Ohio,  People's,  and  Rural. 

District  Shipments. — The  accompanying  data,  furnished  by  the 
Bureau  of  Markets  of  the  United  States  Department  of  Agricul- 


District 


wi: 


1918 


1919  Normal 

estimate*  estimate 


Greely     5,977  cars       5,740  cars       2,500  cars       6,000  cars 

San   Luis  Valley    2,948  cars       3,562  cars       4,400  cars       4,000  cars 

Gunnison  Delta    , 

y 2,380  cars       2,498  cars       2,200  cars       2,500  cars 

and  Montrose 

Carbondale  above 

Glenwood  Spgs.      S>.  .       663  cars  693  cars  525  cars  600  cars 

on  Roaring  Fork 

Eagle  above  I 

Glenwood  Sp<^s.    >■  ■■  ■  534  cars  463  cars  400  cars  500  cars 

on    Main  J 

Grand   Junction    567  cars  516  cars  400  cars  500  ca:rs 

San    Juan    104  cars  46  cars  65  cars  75  cars 

Moffat     112  cars  64  cars  100  cars  100  cars 

Miscellaneous 

Tt    Collin^     y ^^^  '^^^^  ^^^  '^^^^  ^^^  ^^^^  ^^^  ^^^^ 

Dry    Land    j 

*  Estimated  nviniber  of  cars  that  would  be  shipped.    1917  and  1918  data 
represent  actual  shipments. 

ture,  gives  a  fairly  good  idea  of  the  relative  importance  of  the 
principal  shipping  districts  for  the  years  1917,  1918,  and  1919. 

Wyoming. — The  potato  industry  of  Wyoming  is  a  relatively 
small  one,  and  is  largely  restricted  to  the  irrigated  portions  of  the 


148 


POTATO  PRODUCTION  IN  NORTH  AND  WEST 


state.  There  are  no  very  large  producing  centres.  The  leading 
counties,  as  shown  by  the  1909  census  data,  were  Laramie,  Bighorn, 
Sheridan,  Crook,  and  Carbon,  with  yields  ranging  from  203,016 
bushels  in  Laramie  County  to  64,378  bushels  in  Carbon  County. 
Torrington,  in  Goshen  Count}',  is  the  centre  of  one  of  the  more 
recently  developed  irrigation  areas  in  Wyoming.  The  land  in  the 
vicinity  of  Torrington  seems  to  be  admirably  adapted  to  the  potato. 
Some  fields  visited  in  1918  promised  to  yield  around  250  sacks 
(approximately  500  bushels).  A  considerable  acreage  of  potatoes 
M'as  grown  in  the  Cowley  drainage  district  in  Park  County  in  1!)19, 


Fifj.  CS. — Lou  D.  Sweet,  Carbon-  Fig.CQ. — FrankE.Swcct.Carbon- 

(lale,  Col.     A  well  known  authority  dale,  Col.    A  successful  potato  grower 

on  potato  culture.     President  of  the  and  former  partner  of  Lou  D.  Sweet 

Crystal  River  Land  Co.,  better  known  of  the  Crystal  River  Land  Co. 
as  the  Sweet  Ranch,  on  which  high 
yielding  cropaofpotatoesare  annually 
produced. 

and  it  is  claimed  that  there  will  be  a  large  increase  in  1920,  due  to 
the  in,stallatioii  of  a  modern  dehydration  and  starch  factory  at 
that  point. 

Varieties. — The  leading  varieties  grown  in  the  state  are  the 
Pearl,  Spaulding  Xo.  4  (King),  Charles  Downing,  and  the  Eusset 
liurbank   (Netted  Gem). 

Montana. — The  average  total  production  of  ])otatoes  in  Mon- 
tana during  the  teti-year  period  1910  to  1919,  inclusive,  was 
slightly  less  than  5  million  bushels,  with  an  average  acre  yield  of 
125.1  bushels.  There  are  no  extensive  ])roduction  centres.  A  consid- 
erable acreage  of  potatoes  is  grown  in  the  Flat  Mead  Lake  region. 


IDAHO  149 

Varieties. — The  principal  varieties  grown  are  Rural  New  Yorker 
Xo.  2,  Burl)ank,  llus.set  Burbank,  Green  Mountain,  Pearl,  Early 
Ohio,  Triumph,  and  Irish  Col)bler. 

Idaho. — The  potato  crop  of  Idaho  slightly  excels  that  of  Mon- 
tana both  in  total  yield  and  in  production  per  acre.  This  is 
prol)ably  due  to  the  fact  that  a  larger  proportion  of  Idaho's  potato 
crop  is  grown  under  irrigation  than  that  of  Montana.  The  average 
production  for  the  ten-year  period  1910  to  1919  was  5,147,700 
bushels,  and  the  average  acre  yield  was  160.9  bushels.  Idaho  has 
several  distinctive  and  well  recognized  production  centres.  These 
are  in  the  order  of  their  importance,  the  Idaho  Falls,  Burley,  Boise 
(n-  Caldwell,  Blackfoot,  and  Twin  Falls  irrigation  sections. 

In  the  Idalio  Falls  district  there  are  large  tracts  of  warm,  sandy 
soils,  irrigated  with  water  taken  from  the  Snake  River.  No  at- 
tempt is  made  in  this  section  to  produce  an  early  market  crop. 
The  varieties  most  largely  growni  are  the  Russet  Burl^ank  and  the 
Rural  New  Yorker. 

The  Caldwell  district  on  the  Boise  project  is  of  considerable 
importance  as  an  early  market  section.  The  soil  is  for  the  most 
part  a  light  sandy  loam,  well  adapted  to  the  production  of  an 
early  crop.  The  variety  grown  is  the  Charles  Downing  or,  as  it  is 
more  generally  known  in  this  section,  the  Idaho  Rural.  It  is  a 
second-early  or  mid-season  variety,  but  seems  well  adapted  to  its 
environment  in  this  region.  The  growers  hasten  its  maturity 
by  withholding  irrigation  during  early  July  in  order  to  ripen  otf 
the  \anes  and  harden  the  skin.  They  begin  to  dig  the  crop  the  latter 
])art  of  July  or  early  August  and  it  should  all  be  marketed  before 
August  25.  Owing  to  a  combination  of  circumstances,  some  growers 
sustained  rather  heavy  losses  in  1919,  due  to  the  scalding  of  the 
potatoes  in  the  ground  as  a  result  of  their  not  having  been  marketed 
soon  enough.  On  September  10,  the  writer  saw  one  field  in  which 
the  grower  had  sorted  out  fully  50  per  cent  of  the  crop,  and  the 
other  50  per  cent  failed  to  pass  inspection  as  No.  1  stock.  Failure 
to  market  the  crop  at  the  proper  time  was  due  to  a  shortage  of 
refrigerator  cars  in  which  to  transport  the  stock,  and  to  the  scarcity 
of  labor,  thus  delaying  harvesting  operations. 

The  Burley  district  is  the  second  most  imj)ortant  potato  pro- 
duction centre  in  Idaho. 

The  Blachfoot  and  Twin  Falls  districts  are  of  much  less  im- 
portance from  a  commercial  standpoint.     The  only  drawback  to 


150  POTATO  PRODUCTION  IN  NORTH  AND  WEST 

a  large  production  of  potatoes  in  Idaho  is  that  of  its  distance 
from  the  large  consuming  centres. 

Nevada. — Although  the  State  of  Nevada  produces  a  compara- 
tively small  crop  considering  its  geographical  area,  it  is  relatively 
large  when  based  upon  its  population.  The  average  production 
for  the  past  ten-year  period,  1910  to  1919,  was  1,778,100  bushels, 
while  the  population  of  the  state,  as  reported  in  1915,  was 
106,734.  On  this  basis,  the  per  capita  production  was  about 
16%  bushels.  When  this  amount  is  compared  with  the  per 
capita  production  of  the  leading  potato-producing  state  in  the 
Union  of  3.4  bushels,  it  is  seen  that  Nevada's  crop  far  outranks 
that  of  New  York  State,  in  point  of  population  at  least.  Hardman 
states*  that  less  than  2  per  cent  of  the  total  cultivated  area 
of  the  state  is  devoted  to  potatoes,  and  that,  of  the  900,000 
acres  of  irrigated  land,  about  15,000,  or  1%  per  cent  were 
devoted  to  the  potato  crop.  The  average  production  per  acre  of 
170.9  bushels  gives  Nevada  second  place  among  the  states  of  the 
Union,  Maine  alone  surpassing  her  in  this  respect. 

Principal  Poiato  Districts. — The  principal  potato-producing 
districts,  four  in  number,  located  in  the  western  portion  of  the 
state,  are  as  follows:  (1)  Truckee  valley;  (2)  the  Newlands  Ee- 
clamation  Project;  (3)  the  Carson  valley;  (4)  the  Mason  valley. 
According  to  Hardman,  large  areas  of  the  Newlands  Keclamation 
Project,  and  the  Mason  valley  are  excellently  adapted  to  po- 
tato culture. 

Bate  of  Planting.— The  bulk  of  the  crop  is  planted  during  the 
middle  of  May,  and  is  generally  com])leted  by  the  first  of  June. 

Varieties. — The  principal  varieties  grown  are  the  Eural  New 
Yorker  No.  2,  Burbank,  Eusset  Burbank,  Pearl,  Early  Ohio. 

Arizona. — The  state  of  Arizona  has  the  distinction  of  being 
the  tail-ender  in  potato  production.  Its  average  annual  production 
for  the  ten-year  period,  1910  to  1919,  is  only  181,500  bushels  with 
an  average  acre  yield  of  86.4  bushels.  Potato  production  in  the 
state  at  the  present  time  is  on  the  increase.  In  fact,  the  Bureau 
of  Crop  Estimates'  statistics  note  an  acreage  increase  of  500  per 
cent  since  1916.  A  small  industry  is  being  developed  near 
Flagstaff,  in  Coconino  County,  and  Glendale,  in  Maricopa  County. 

In  the  southern  part  of  the  state,  the  early  crop  is  planted  from 
January  15  to  February  15 ;  and  the  fall  crop,  from  August  20 
to  September  10.    The  early  crop  must  be  out  of  the  ground  before 


WASHINGTON  151 

July  1,  as  it  deteriorates  very  rapidly  with  the  advent  of  extremely 
hot  summer  weather.  The  early  crop  is  usually  consumed  before 
July  4. 

New  Mexico, — Potato  growing  in  New  Mexico  is  a  rather 
unpromising  industry,  owing  to  the  many  failures  that  are  incurred 
through  the  non-development  of  marketable  sized  tubers.  These 
failures  usually  occur  in  hot  dry  seasons,  aud  are,  in  most  cases, 
probably  entirely  due  to  unfavorable  climatic  conditions.  In 
some  cases,  fungous  diseases  inhabiting  soils,  such  as  Fusaria  and 
Ehizoctonia,  are  no  doubt  responsible  for  lack  of  success  in  produc- 
ing a  profitable  crop  of  potatoes.  The  annual  production  during 
1910  to  1919  was  7G9,200  bushels  with  an  average  yield  per  acre 
of  88.4  bushels.  The  largest  production  centre  is  Cloudcroft  in 
Otero  County.    The  Irish  Cobbler  is  the  principal  early  variety. 

Neither  New  Mexico  nor  Arizona  are  ever  likely  to  become  im- 
portant potato-producing  states. 

Utah. — The  State  of  Utah  ranks  seventh  in  point  of  production 
among  tlie  eleven  far-western  states.  Utah,  Davis,  Salt  Lake, 
Cache,  and  AVeber  Counties  are  the  largest  production  centres. 
The  average  annual  production  during  the  period  of  1910  to  1919 
was  3,058,900  bushels,  with  an  acre  yield  of  161.8  bushels. 

The  principal  varieties  grown  are  tlie  Charles  Do-\vning  (Idaho 
Eural),  Russet  Burbank,  and  Rural  New  Yorker  No.  2. 

Oregon. — The  State  of  Oregon  has  two  rather  distinctive  types 
of  climatic  conditions,  the  eastern  portion  having  a  jDractically 
semi-arid  climate,  while  the  western  portion  has  a  more  or  less 
humid  one.  The  average  annual  production  of  the  state  for  the 
years  1910  to  1919  was  6,377,800  bushels  with  an  average  acre 
yield  of  121  bushels.  The  largest  production  centres  are  located 
in  Multnomah,  Marion,  Clackamas,  Washington,  Lane,  and  Lin- 
coln Counties. 

The  leading  varieties  grown  are  the  Pride  of  Multnomah 
(Burbank  type),  Russet  Burbank,  White  Rose,  Early  Ohio,  Rural 
New  Yorker  No.  2  and  American  Wonder  (Burbank  type). 

Washington. — The  climatic'  conditions  in  Washington  State 
are  very  similar  to  those  in  Oregon,  in  that  the  western  portion  is 
humid  and  the  eastern  part  semi-arid.  There  are  two  rather 
well  recognized  irrigated  sections,  the  Yakima  and  Wenatchee  Val- 
leys, which  produce  considerable  quantities  of  potatoes.  The  aver- 
age annual  production  of  the  state  for  1910  to  1919  was  8,441,300 


152  POTATO  PRODUCTION  IN  NORTH  AND  WEST 

bushels  with  an  acre  yield  of  139.3  bushels.  The  leadiiicj  produc- 
tion centres  are  located  in  Yakima,  Spokane,  Skagit,  King,  and 
Whitman  Counties. 

The  leading  varieties  are  the  Russet  Burbank,  Charles  Downing, 
Early  Ohio,  and  Rural  New  Yorker  No.  2. 

California. — The  state  of  California  enjoys  the  distinction  of 
having  a  greater  variety  of  climatic  conditions  than  any  other 
state  in  the  Union.  In  the  southern  portion  of  the  state,  it  is 
possible  to  produce  a  crop  of  ])otatoes  about  as  early  as  in  southern 
Florida;  while  in  the  more  elevated  portions  of  the  northern  part, 
the  frost-free  season  is  hardly  of  sufficient  length  to  permit  of 
maturing  a  crop.  It  is  not  strange,  therefore,  that  many  problems 
confront  the  California  potato  grower.  In  point  of  production, 
California  leads  all  others  of  the  far-western  states,  with  an  average 
annual  yield  for  the  years  1910  to  1919,  of  10,652,400  bushels,  and 
an  acre  i)roduction  of  134.7  bushels.  The  chief  production  centres 
are  San  Joaquin,  Los  Angeles,  Sacramento,  Contra  Costa,  and 
Santa  Cruz  Counties.  Of  these  centres  San  Joaquin  and  Los 
Angeles  are  the  most  important.  The  potato  crop  in  San  Joaquin 
County  is  produced  on  the  reclaimed  "tule"  lands  in  the  delta 
sections  of  the  San  Joaquin  and  Sacramento  rivers. 

First  crops  on  reclaimed  lands  will  frequently  run  300  sacks 
per  acre.  The  sack  will  average  about  115  pounds.  In  Los  Angeles 
County  it  is  possible  to  plant  potatoes  for  the  early  market  during 
January,  and  to  harvest  the  crop  in  the  latter  part  of  March  and 
early  April.  A  second  crop,  planted  in  late  July  or  August,  is  also 
grown  in  this  section,  and  is  harvested  in  November. 

The  Potato  King. — The  story  of  the  Stockton  potato  district, 
San  Joaquin  County,  would  not  be  complete  were  we  to  fail  to 
mention  the  "potato  king,"  of  the  Pacific  Coast,  Mr.  George  Shima, 
who,  not  so  many  years  ago,  emigrated  to  California  from  Japan 
and  became  a  day  laborer  on  these  reclaimed  lands.  The  story  of  his 
rise  from  a  day  laborer  to  the  largest  potato  grower  and  potato 
operator  on  the  Pacific  Coast  is  one  which  should  thrill  every  am- 
bitious American  youth.  Some  years  ago,  Mr.  Shima  was  growing 
8,000  acres  of  potatoes.  The  writer  was  on  one  tract  of  4,400 
acres,  in  the  spring  of  1910,  which  was  being  fitted  for  planting 
to  potatoes  by  Shima's  crew  of  laborers. 

Harvesting  the  Crop. — The  usual  method  of  digging  the  crop 
is  with  a  heavy  five  or  six-pronged  hoe  fork,  so  constructed  as  to 


CALIFORNIA  153 

be  used  in  the  same  manner  as  a  hoe.  Each  digger  picks  up  the 
tubers  as  they  are  dug.  Large  and  strongly  made  wicker  baskets 
serve  as  containers  for  the  tubers.  When  full,  the  contents  of  the 
basket  is  transferred  to  a  two-bushel  burlap  bag.  The  sacks  are 
well-filled,  and  the  digger  usually  faces  the  mouth  of  the  sack  with 
extra  large  and  well  shaped  tubers.  When  the  market  is  dull  at 
digging  time  and  the  stock  grown  is  sound,  it  is  frequently  stored 
in  large  piles  on  the  levee  and  covered  with  "tule"  grass,  to  protect 
the  tubers  from  the  light  frosts  that  occur  in  this  region  during 
the  winter  season,  and  from  light.  A  large  proportion  of  the  crop 
is  moved  to  the  market  in  boats  in  much  the  same  manner  as  in 
the  Norfolk  district,  though  the  Stockton  district  is  practically 
all  accessible  to  water. 

QUESTIONS  ON  THE  TEXT 

1.  Why    does    the    potato    succeed    best    in    the    northern    part    of    the 

temperate   zone  ? 

2.  What   bearinfj  has   altitude  on   potato  production? 

3.  What  are  the  leading  potato-producing  states? 

4.  What  percentage  of  the  crop  is  produced  by  the  six  leading  states? 

5.  What  are  the  two  important  factors  aft'ecting  heavy  or  light  production  ? 

6.  How  does  the  average  production   per   acre  of   the   far-western   states 

compare  with  that  of  the  six  heavy  producing  states? 

7.  How  does  the  production  of  Aroostook  County,  Maine,  compare  with  the 

total  production  of  other  states?     Explain  this. 

8.  What  is  the  general  character  of  the  soil  of  Aroostook  County,  Maine? 
0.  What  are  the  leading  commercial  varieties  grown  in  Maine?     Secondary 

varieties? 

10.  Is  there  any  similarity  between  the  Long  Island,  N".  Y.,  and  the  New 

Jersey  districts?     What  is  it? 

11.  What  are  the  chief  points  of  differences  between  these  two  districts  and 

that  of  northern  Maine? 

12.  What  are  the  leading  varieties  grown  in  these  districts? 

13.  What  are  the  chief  producing  centres  in  New  Jersey? 

14.  ^^■hat   is  the  chief  ])roduction  centre  on  Long  Island,   N.   Y.  ? 

13.  What  is  the  character  of  the  soil  in  the  more  intensive  potato-producing 

areas  on  Long  Island  and  in  New  Jersey? 
10.  How  do  the  climatic  conditions  of  these  compare? 

17.  What  is  the  source  of  seed  supply  of  these  two  sections? 

18.  Do  the  New  England  States,  Maine  excepted,  produce  any  considerable 

quantity  of  seed  potatoes?     Why? 

19.  Are  early  varieties  grown  to  any  considerable  extent  in  western  New 

York  and  Pennsylvania?     Give  reason. 

20.  What   does   a   comparison   of  production   in   these  two   states   for   the 

years  1910  to  1919  show? 

21.  What  varieties  are  most  commonly  grown? 

22.  What  did  Stone's  investigations  with  level  and  ridge  culture  disclose? 

23.  How  do  they  store  their  crop  of  potatoes? 


154  POTATO  PRODUCTION  IN  NORTH  AND  WEST 

24.  Of  what  importance  are  the  States  of  Ohio,  Indiana,  Illinois,  Iowa  and 

Missouri   from   the   production   standpoint? 

25.  Compare  their  yields  per  acre  with  Lon<j  Island. 

26.  Name  some  of  the  larger  producing;  counties  in  Ohio. 

27.  What   are  the   leading   coimties   in   Illinois? 

28.  What   are   the   leading   counties    in    Iowa? 

29.  What  are  the  leading  counties  in  ^Missouri? 
80.  What  are  the  leading  counties  in   Indiana? 

31.  What  can  you  say  regarding  the  use  of  commercial  fertilizers  in  these 

five  states? 

32.  What  is  the  common  system  of  culture? 

33.  Where  do  they  usually  market  their  crops? 

34.  On  what  states  are  they  largely  dependent  for  their  seed  stock? 

35.  In  what  respects  are  Michigan,  Wisconsin  and  Minnesota  quite  similar 

as  rega-/(s  potato  production? 

36.  What  are  the  distinctive  and  widely  known  potato  districts   in  these 

states  ? 

37.  What  is  the  most  interesting  feature  relative  to  the  annual  production 

of  these  states? 

38.  What  are  the  leading  commercial  varieties  grown   in  these  states? 

39.  What  can  be  said  of  the  seed  trade  in  these  states  ? 

40.  What  are  the  cultural  practices  in  this  group  of  states? 

41.  Discuss  the  yields  of  each  of  the  next  group  of  states. 

42.  What    special    interest   have   these   four    states   over   those    previously 

considered  ? 

43.  What  are  the  chief  production  sections  in  each? 

44.  What  are  the  leading  commercial  varieties  in  these  states? 

45.  In  what  part  of  each  of  these  states  is  the  Early  Ohio  grown? 

46.  In  what  state  is  the  Triumph  most  extensively  grown?     Where   sold 

for   seed? 

47.  Name   the  eleven   far-western   states. 

48.  Which  are  the  largest  producing  states? 

49.  What  particular  distinction   does   Colorado  possess? 

50.  What  two  classes  of  potato  production   do  we  have   in   these  states? 

51.  What  similarity  is   found  in   Washington  and   Oregon  to  that  of  the 

north-eastern  United  States? 

52.  Which  of  the  eleven  states  leads  in  total  production  per  acre  and  which 

in  average  bushels  per  acre? 

53.  What  are  the  leading  commercial  varieties  in  Arizona  and  New  Mexico? 

54.  What  are  the  leading  commercial  varieties  in  California  and  Colorado? 

55.  Name  some  of  the  potato  districts  in  Colorado. 

56.  Of  what  importance  is  the  potato  industry  in  Wyoming? 

57.  What   was   the   average   production    of   Montana    during    the    ten-year 

period   1910  to  1919? 

58.  What  are  the  principal  varieties  grown? 

59.  What  is  the  extent  of  the  Idaho  crop? 

60.  What  is  the  special  feature  of  interest  regarding  the  Caldwell  district? 

61.  Of  what  relative  importance  is  the  potato  crop  of  Nevada? 

62.  Compare  its  per  capita  production  with  that  of  New  York. 

63.  What  percentage  of  the  cultivated  area  of  the  state  is  devoted  to  potatoes  ? 

64.  What  is  the  average  production  per  acre? 

65.  Discuss   potato   growing    in   Arizona. 

66.  Discuss  potato  growing  in  New  Mexico. 

67.  Give  aimual  production,   leading  counties  and   varieties   for   Utah. 


QUESTIONS  ON  THE  TEXT  155 

68.  Give    the    annual    production,    largest    centres    and    leading    varieties. 

69.  Name  two  well   recognized   irrigated   districts   in   the   state  of   Wash- 

ington. 

70.  Give   the   average   annual   production,    leading   counties    and   varieties 

of  Washiijgton. 

71.  For  what  is  the  state  of  California  noted  climatically? 

72.  Discuss  its  production  and  chief  centres. 

73.  How   many    sacks    per    acre   do    they    sometimes    harvest    from    newly 


reclaimed  laud? 


References   Cited 


1.  Anonymous.     1916.     U.  S.  Bur.  Crop  Estimates.     Mo.  lint   Nov     1916- 

116,  251.  f  ;  ■ 

2.  Ballou,   F.  H.      1910.     The   status  of  the  potato-growing   industry   in 

Ohio.     Ohio  Sta.  Bui.  218:  561-595,  June,  1910. 

3.  Green,  S.  N.     1917.     Potato  growing.     Ohio  Sta.     Mo.  Bui.  5:    148-149. 

jMay,  1917. 

4.  Hardman,  G.     1920.    Nevada's  75,000  ton  potato  crop.    Pot.  Maa   2-   17 

Feb.,  1920.  i-  r  y  , 

5.  Roberts,  I.   P.,  and   L.  A.   Clinton.      1897.     Potato   Culture.     N.    Y. 

{Cornell)  Sta.  Bui.  130:  151-163,  March,  1897.  1897.  Second 
Report  on  potato  culture.  N.  Y.  (Cornell)  Sta.  Bui.  140:  385-406, 
Nov.,  1897.  1898.  Third  Report  on  potato  culture.  N.  Y.  (Cor- 
nell) Sta.  Bui.  156:  175-184,  Dec,  1898.  1901.  Fourth  Report 
on  potato  culture.   A^  Y.   (Cornell)  Sta.  Bui.  196:  43-59,  Nov.,  1901. 

6.  Stone,  J.   L.     1905.     Potato  growing  in  New  York.     N.   Y.    (Cornell) 

Sta.  Bull.  228:  445,  April,  1905. 

7.  Westover,  H.  L.,  and  Rowe,  R.  W.     1910.     Soil  Survey  of  the  Caribou 

Area,  Maine.     U.  S.  Dept.  Ayr.  Bur.  Soils.     (1908)  :  20,  July,  1910, 


chaptp:r  XI 

POTATO  PRODUCTION  COSTS 

Business  Principles. — The  sueecssful  conduct  of  any  manu- 
facturing enterprise  is,  in  a  large  measure,  dependent  upon  two 
factors :  (1)  Low  cost  of  production  consistent  with  the  manufacture 
of  a  good  article;  and  (2)  the  successful  merchandising  of  the 
manufactured  })roduct.  If  we  regard  the  farmer  as  a  manufacturer 
of  raw  food  products,  or  at  least  as  an  instrument  to  that  end, 
then  we  may  regard  the  production  of  potatoes  in  the  same  light 
as  that  of  the  manufacture  of  potato  machinery,  in  that  the  same 
general  husiness  principles  ajji^ly  to  each.  In  fact,  there  are  greater 
opportunities  for  the  exercise  of  good  judgment  and  the  intelligent 
application  of  modern  principles  of  agriculture  in  the  manufacture, 
if  we  may  so  employ  the  term,  of  a  crop  of  potatoes  than  in  the 
building  of  the  most  complicated  implement  used  in  the  potato 
industry.  The  manufacturer  of  the  latter  has  complete  control 
of  all  the  factors  involved  in  the  construction  of  such  an  implement ; 
while  in  the  case  of  the  potato  grower  or  manufacturer,  there  are 
at  least  two  factors,  temperature  and  moisture,  over  which  he  can 
exercise  little  or  no  control,  unless  he  is  fortunate  enough  to  be 
located  in  an  irrigated  section,  thereby  making  it  jwssible  to  supply 
moisture.  In  Chapter  IV,  an  attempt  is  made  to  show  how  the 
grower  may  modify  unfavorable  temperature  and  moisture  condi- 
tions ;  hence  no  further  attention  need  be  given  to  these  factors. 

Cost  Per  Acre  Misleading. — In  most  discussions  dealing  with 
the  cost  of  producing  potatoes,  greater  stress  has  been  laid  upon  the 
production  cost  per  acre  than  on  the  cost  per  bushel  or  per  pound. 
The  statement  that  it  cost  $150,  $175,  $200  or  $225  to  grow  an  acre 
of  potatoes  may  mean  much  or  little,  according  to  whether  it  carries 
with  it  the  additional  information  as  to  the  yield  obtained  in  each 
case.  The  man  who  grew  an  acre  of  potatoes  for  $150  and  only 
produced  150  bushels,  cannot  be  regarded  as  successful  as  one 
whose  acre  cost  was  $225  and  production  400  bushels.  In  the  first 
instance,  the  actual  cost  per  bushel  was  $1.00,  while  in  the  latter, 
it  was  only  $0.5625.  A  comparison,  therefore,  of  ])roduction  costs 
per  acre  affords  no  conclusive  evidence  of  the  actual  cost  per 
156 


COST  FACTORS  IN  POTATO  PRODUCTION  157 

bushel,  unless  aceonipaiiied  by  the  further  information  as  to  the 
yield  obtained. 

Cost  Factors  in  Potato  Production. — In  arriving  at  a  proper 
and  fair  cost  basis  in  the  production  of  an  acre  or  a  bushel  of 
])otatoes,  it  is  necessary  to  determine  what  items  of  cost  should 
l)e  proi)erly  charged  against  the  crop.  These  may  be  roughly 
grouped  under  nine  heads,  viz.:  (1)  labor;  (2)  materials;  (3)  in- 
terest; (i)  insurance;  (5)  taxes;  (6)  depreciation;  (7)  overhead; 
(8)  risk;  (9)  miscellaneous  items.  Under  the  first  head  would 
be  included  hand  and  horse  labor  necessary  to  the  plowing  and 
fitting  of  the  land,  the  application  of  fertilizers,  seed  cutting,  plant- 
ing, cultivation,  spraying,  harvesting,  storing,  grading  and  market- 
ing of  the  crop.  The  second  head  includes  the  cost  of  the 
chemical  fertilizers  or  farmyard  manures  applied  to  the  land,  seed, 
spray  materials,  and  containers  used  in  marketing  the  crop.  The 
tliird  charge  represents  interest  on  investment,  which  should  include 
not  only  the  land,  but  every  implement  and  building  or  storage 
space  used  in  handling  the  crop.  Too  often  this  charge  only  applies 
to  the  land.  Insurance  apjilies  to  equipment,  storage  house,  and 
the  crop  itself  when  stored  for  winter  or  spring  marketing.  Taxes 
are  self-explanatory;  they  represent  the  actual  assessments  on  real 
estate  and  ])ersonal  property  involved  in  the  ])roduction  of  the 
crop.  Depreciation  in  the  value  of  implements  used  in  the  growing 
of  potatoes  should  be  based  on  the  average  life,  if  we  may  so  term 
it,  of  each.  If,  for  example,  this  average  life  is  300  acres  of 
l)otatoes,  then  one-three-hundredth  of  the  value  of  the  implement 
should  be  charged  against  each  acre.  In  the  case  of  the  seventh 
item,  a  slightly  different  problem  is  presented.  This  is  a  charge 
which  is  generally  overlooked  by  the  grower  in  determining  his 
production  costs.  In  all  manufacturing  establishments,  overhead 
expenses  is  one  of  the  most  important  items  in  production  costs. 
There  is  no  good  reason  why  the  producer  of  agricultural  crops 
should  not  assess  a  fair  charge  against  each  crop  over  which  he 
exercises  supervision,  instead  of  simply  charging  against  the  crop 
the  actual  hours  of  man  labor  devoted  to  the  growing  and  handling 
of  it.  The  producer  should  regard  his  services  or  his  time  as  having 
a  certain  fixed  value  throughout  the  year,  and  all  time  not  actually 
devoted  to  any  crop  should  be  pro-rated  against  each  crop  grown 
on  the  farm  on  the  basis  of  the  actual  cost  of  producing  such  crops. 

Tlie  potato  crop  sliould  also  ])ear  its  proportional  share  of  the 


158  POTATO  PRODUCTION  COSTS 

maintenance  cost  of  horses  or  mules  necessary  to  the  proper  opera- 
tion of  the  farm,  during  that  portion  of  the  year  in  which  they  are 
idle;  for  example,  rainy  days,  Sundays  and  in  the  winter  season. 
Eainy  days  and  Sundays  may  he  taken  care  of  through  a  high 
enough  horse  labor  charge  per  hour  or  per  diem,  for  actual  work 
performed,  but,  as  a  rule,  it  is  not  completely  covered  by  such 
charges.  By  risk  is  meant  that  element  of  uncertainty  as  to  the 
extent  of  the  crop  that  will  be  produced.  The  producer  of  agricul- 
tural crops  is  engaged  in  a  business  that  is  fraught  with  greater  ele- 
ments of  risk  than  that  of  almost  any  other  business  enterprise, 
unless  it  be  that  of  prospecting  for  oil  or  minerals.  The  potato 
crop  is,  perhaps,  a  riskier  one  to  grow  than  any  other  food  crop, 
because  it  is  so  easily  affected  by  drought,  heat  and  frost,  fungous 
diseases,  and  insect  pests.  Any  one  of  these  conditions  may  seri- 
ously reduce  the  crop  and  render  it  a  liability,  instead  of  an  asset, 
in  the  farm  account  book.  It  is  believed  that  a  certain  fixed  charge 
should  be  assessed  against  the  potato  crop  each  year  as  a  provision 
against  monetary  loss.  What  such  a  charge  should  be  must  be 
determined  for  each  locality.  The  prevalence  of  droughty  or  of 
high  temperature  periods  during  the  growing  season,  or  of  serious 
outbreaks  of  late  blight  or  other  serious  diseases,  or  of  insect 
pests  must  be  taken  into  consideration  in  arriving  at  a  just  and  fair 
risk  compensation.  To  the  miscellaneous  items  account  should  be 
charged  all  expenses  connected  with  the  repairing  of  farm  imple- 
ments or  of  buildings  used  in  the  gro^vang,  handling,  or  storing 
or  marketing  of  the  crop.  It  should  also  include  any  other  items 
of  expense  not  specifically  provided  for  under  the  other  heads. 

Average  Production  Cost. — Any  attempt  to  present  a  set  of 
data,  which  would  adequately  represent  the  average  cost  of  pro- 
ducing a  bushel  of  potatoes  in  the  United  States,  or  elsewhere,  is 
obviously  impossible ;  local  conditions  are  so  variable  that  such  data 
would  have  little  practical  value  except  for  the  actual  locality  upon 
which  the  cost  data  was  based. 

In  1916,  App  ^  published  the  results  of  a  rather  comprehensive 
study  of  the  relation  of  the  potato  crop  to  farm  profits.  In  the 
pursuit  of  this  study,  App  took  data  on  the  operating  costs  and 
income  of  some  370  potato  farms.  While,  according  to  the  author, 
(p.  68)  no  work  was  done  to  determine  the  actual  acre  and  bushel 
cost  of  producing  potatoes  on  the  370  farms,  there  were  25  of  these 
farms  from  which  practically  nothing  but  potatoes  were   sold. 


AVERAGE  PRODUCTION  COST 


159 


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160  POTATO  PRODUCTION  COSTS 

The  receipts,  other  than  from  ]iotatoos,  on  these  farms  averaged  less 
than  8  per  cent,  and  in  arriving  at  the  actual  cost  per  bushel  or 
per  barrel,  A])p  deducted  this  revenue  from  the  total,  thereby 
arriving  at  a  figure  which  he  believes  to  be  quite  representative 
of  the  production  cost  of  potatoes  in  Monmouth  County,  New 
Jersey.  His  data  shows  a  cost  of  93  cents  per  barrel  or  33  cents 
per  bushel. 

App's  Cost  Data. — The  ])roduction  costs  given  by  App  in  the 
following  table  are,  in  his  Judgment,  fairly  representative  of  this 
section  in  1914.  They  show  a  total  production  cost  per  acre  of 
$85.15,  and  a  total  income  of  $123.48,  leaving  a  net  profit  of 
$38.33  per  acre.  The  average  ])rice  received  for  the  potatoes  on 
these  farms  was  $1.45  per  barrel,  and  the  average  labor  income  of 
these  farms  was  $2,123.00. 

Acre  cost  of  producing  potatoes  on  2.7  potato  farms  in  Monmouth  Counti/, 
Nev  Jersey. 

Total  acres  of  potatoes  on  the  25  farms 919 

Labor  expense  per  acre $21.58 

Cost  of  potato  seed— 485  bbl 10.76 

Fertilizer  expense 24.95 

Machinery   depreciation 2.35 

Spraying  materials 0.51 

Barrels   0.55 

Clover   crop   seed 0.73 

Taxes    3.10 

Insurance     0.94 

Interest    21.72 

Grass  seed  per  acre 0.92 

Miscellaneous    7.(52 


Total    acre    expenses  $95.72 

Brought   forward $95.72 

Receipts  from  crops  other  than  potatoes,  divided  by  the 

number  of  acres  of  potatoes 10.57 


Cost    per    acre    of    potatoes  $85.15 

Yield   per  acre 92.1  bbl. 

Cost  per  barrel   0.92 

Cost  per  bushel    0.33 

Fox's  Cost  Data. — One  of  the  most  exhaustive  studies  upon 
the  cost  of  producing  potatoes  that  has  come  to  the  writer's  at- 
tention is  that  recently  published  by  Fox,-  in  which  a  digest 
of  the  cost  of  producing  potatoes  on  355  farms  in  Steuben,  161 
in  Suffolk,  and  41  in  Nassau  Counties  in  1912;  300  in  Clinton  and 


FOX'S  COST  DATA  161 

Franklin  counties  in  1913;  and  26  records  on  20  cost  account 
farms  in  1913,  1914  and  1915,  is  presented. 

The  following  analysis  of  Fox's  tables  presents  the  more  salient 
features  of  these  data.  The  comparison  of  costs  in  the  several 
localities  from  which  his  figures  Avere  secured  is  very  interesting. 

In  studying  these  data,  it  is  important  to  bear  in  mind  that 
these  costs  were  obtained  in  pre-war  times,  when  the  price  of  labor, 
fertilizer  and  all  other  factors  entering  into  ])otato  production  were 
from  50  to  100  per  cent  less  than  in  1920.  The  small  amounts  of 
manure  and  commercial  fertilizer  used  in  Steuben,  Clinton  and 
Franklin  Counties,  is  due  to  the  fact  that  relatively  few  of  the  655 
farmers  involved  used  either  one  or  the  other.  The  same  thing  is 
true  with  respect  to  the  use  of  fungicides  and  insecticides.  For 
example,  Fox  states  that  only  180  of  the  355  Steuben  County 
farmers  sprayed  their  potatoes,  and  that  Bordeaux  mixture  was  only 
used  on  17  farms.  Peacock's  (I.e.)  data  show  that  203  of  the  300 
Clinton  and  Franklin  County  farmers  sprayed  their  potatoes  with 
arsenical  ])oisons,  and  only  three  sprayed  with  Bordeaux  mixture. 
An  interesting  feature  of  these  data  is  that  of  the  wide  variation 
in  the  average  cost  of  growing  an  acre  of  potatoes.  Tlie  average 
cost  in  Steuben  County  being  $51.13,  as  against  $113.51  in  Nassau 
County  or  an  increase  of  122  ])er  cent.  The  cost  per  bushel  varied 
from  37  to  61  cents  or  a  difference  of  nearly  65  per  cent.  The 
significance  of  these  figures  is  not  fully  appreciated  until  they  are 
compared  with  their  selling  value.  For  example,  the  355  Steuben 
County  farmers  produced  potatoes  on  5,227.1  acres  at  an  average 
cost  of  $0.4201  per  bushel ;  for  which  they  received  a  return  of 
$0.4403  per  bushel,  thereby  netting  a  trifle  over  two  cents  per 
l)ushel,  or  a  total  return  of  $2.46  per  acre.  The  161  Suffolk  County 
farmers,  on  their  3,149.7  acres,  produced  potatoes  at  an  average 
cost  of  $0.5426  per  bushel;  for  which  they  received  a  return  of 
$0.7055  or  a  net  profit  of  $0.1629.  The  total  return  per  acre  was 
$25.66.  Nassau  County  growers,  of  whom  there  were  41  with  an 
aggregate  of  1,466.3  acres,  grew  potatoes  at  an  average  cost  of 
$0,607  per  bushel;  for  which  they  received  a  return  of  $0.7495, 
or  a  net  profit  of  $0.1425  and  a  total  return  of  $26.66.  The  300 
CUnton  and  Franklin  County  growers,  on  2,160  acres,  produced 
potatoes  at  an  average  cost  of  $0.3898 ;  for  which  they  received  a 
return  of  $0.5784  per  bushel,  or  a  net  total  profit  of  $36.29  per  acre. 
The  average  of  the  26  records,  from  the  20  cost  account  farms. 


1G2  POTATO  PRODUCTION  COSTS 

showed  an  actual  cost  of  $0.4202  per  bushel,  witli  returns  of 
$0.5158;  or  a  net  profit  of  $0.0956  per  bushel,  ami  u  total  profit 
of  $7.92  per  acre. 

One  of  the  most  important  economic  lessons  to  be  deducted 
from  these  data  is  that  it  was  more  profitable  for  the  Nassau 
County  farmers  to  produce  potatoes  at  a  cost  of  nearly  61  cents  per 
bushel,  than  it  was  for  the  Steuben  growers  at  42  cents.  This 
was  made  possible  through  the  wide  difference  in  price  received 
for  their  crop  by  these  two  groups  of  growers.  Had  the  Nassau 
growers  been  compelled  to  dispose  of  their  crop  at  the  same  price 
as  that  received  by  the  Steuben  growers,  they  would  have  sustained 
an  actual  loss  of  $34.95  per  acre,  instead  of  realizing,  as  they  did, 
a  profit  of  $26.66,  It  is  obvious  from  these  data  that  low  cost 
of  production  is  not  necessarily  correlated  with  a  large  net  profit 
per  acre.  Proximity  to  large  consuming  centres,  where  advantage 
can  be  taken  of  a  strong  market,  may  make  potato  production 
a  more  profitable  undertaking,  even  at  a  greatly  increased  cost  per 
bushel,  than  in  a  remote-from-market  section,  where  the  grower 
is  more  or  less  dependent  upon  local  buyers  for  the  disposal  of 
his  croi>. 

Pelton's  Cost  Data. — At  a  meeting  of  the  Connecticut  Vege- 
table Growers  Association,  in  February,  1918,  some  cost  figures 
on  potato  production,  based  on  rather  small  areas,  were  presented 
by  Pelton;-*  in  which  it  was  shown  that,  under  Connecticut  condi- 
tions, the  cost  of  growing  potatoes  was  greater  on  very  small  areas 
than  on  larger  ones.  Three  sets  of  cost  data  were  submitted,  one 
being  based  on  a  half  acre,  another  on  one  acre  and  the  third  on  nine 
acres.  These  data,  as  assembled  in  the  next  table,  show  that  it 
cost  $132.16  to  grow  half  an  acre,  or  at  the  rate  of  $264.32  i)er 
acre;  $171.55  for  an  acre;  and  $166.55  on  a  nine-acre  basis.  Strik- 
ing variations  in  the  cost  of  the  same  item  in  the  three  sets  of 
data  may  be  noted  in  this  table.  For  example,  in  the  digging  and 
storing  of  the  crop,  the  cost  varies  from  $20.00  per  acre  on  the 
nine-acre  field  to  $46.50  on  the  acre  field  and  $31.24  on  the  half 
acre,  or  at  the  rate  of  $62.48  per  acre. 

These  figures  are  interesting  in  that  they  illustrate  very  forcibly 
the  impossibility  of  producing  potatoes  cheaply  on  small  areas 
where,  of  necessity,  much  of  the  labor  must  be  performed  by  hand. 
It  also  emphasizes  the  fact  that  the  small  grower  cannot  success- 
fully  compete  with  the  large   grower,   provided  the  latter   uses 


NORDMAN'S  COST  DATA 


163 


modern  machinery  and  handles  his  crop  intelligently.  Potato  pro- 
duction on  a  small  acreage  basis  with  a  large  amount  of  man  labor 
is  only  justifiable  where  the  crop  is  primarily  grown  for  family  use, 
or  where  nearby  markets  absorb  it  at  practically  retail  prices. 

Nordman's  Cost  Data. — A  rather  recent  article  by  Nordman^ 
contains   some   interesting  information   upon   the    cost   of   potato 


Cost  of  Potato  Production  in  Connecticut  in  1917,  by  W. 

C.  Pelton. 

Cost  factors 

One-half  acre  fielc 

One-acre  field 

Nine-acre 
field 

Fitting  land 

$  6.20 

$  10.40 

$  10.00  per  a. 

Planting  &  cost  of  seed .... 

61.60 

06.50  per  a. 

Seed  at  $2.90  and  hauling 

seed  at  $0.88 

15.38 

Cutting  seed 

1.64 

Labor  in  planting ... 

3.48 

Fertilizer  &  manure 

31.00 

40.05  per  a. 

Ten  loads  manure 

10.00 

Hauling  manure  &  spread- 

ing by  hand  

42.68 

Cultivation  &  hoeing 

4.48 

13.85 

15.00  per  a. 

1  65 

8.20 

15.00  per  a. 

Digging  &  storing 

15.62 

46.50 

20.00  per  a. 

Marketing 

13.23 

Interest  on  valuation 

($400.00  per  acre) .... 

12.00 

Overhead  expense  and .... 

taxes 

5.80 

Total  cost .... 

$132  16 

$171  55 

$166  55 

Yield 

150  bu. 

170  bu 

production  in  Wisconsin.  At  a  hearing  in  Milwaukee,  on  April 
23,  1920,  conducted  by  the  Wisconsin  Division  of  Markets,  the 
testimony  given  by  potato  growers  on  the  cost  of  growing  potatoes 
in  1919,  showed  a  wide  range  of  variation.  The  lowest  estimated 
cost  was  56  cents  per  bushel,  while  the  highest  was  $2.57  per  bushel. 
In  the  latter  case,  the  high  production  cost  was  due  to  the  yield, 
which  was  cut  dowai  to  30  bushels  per  acre  as  a  result  of  unfavorable 
crop  conditions.  The  average  cost  per  bushel  of  those  testifying 
was  78  cents  per  bushel. 


164  POTATO  PRODUCTION  COSTS 

The  low  cost  of  production,  5G  cents  per  bushel,  was  reported 
by  one  of  the  best  growers  in  the  state,  whose  average  production 
per  acre  was  250  bushels. 

It  must  be  evident  to  the  reader,  from  even  the  limited  amount 
of  data  presented,  that  cost  of  production  is  directly  correlated  with 
yields ;  and  that  yields  per  acre  are  largely  dependent  upon  the  skill 
and  intelligence  of  the  grower.  In  certain  secti,ons  of  the  country, 
where  the  soil  and  climatic  conditions  are  favorable  and  the  land 
well  supplied  with  plant  food,  the  skilful  grower  will  inevitably 
produce  a  crop  of  potatoes  at  a  much  lower  cost  ])er  bushel  than  will 
some  other  grower,  equally  skilful,  who  attempts  to  grow  potatoes 
under  less  favorable  soil  and  climatic  conditions.  I  am  firmly 
convinced  that  the  only  solution  of  the  present  high  cost  of  produc- 
tion is  that  of  increasing  the  yield  per  acre  through  the  use  of 
high  grade  seed,  and  the  adoption  of  up-to-date  methods  of  cul- 
ture, harvesting,  and  marketing  of  the  crop.  When  the  average 
})roduction  of  some  of  our  largest  producing  states  is  raised  to  150 
or  200  bushels  per  acre,  instead  of  from  85  to  95  as  at  present, 
the  question  of  cost  per  bushel  and  net  returns  per  acre  will  have 
been  satisfactorily  solved. 

QUESTIONS    ON    THE   TEXT 

1.  Upon  what  two  factors  is  the  successful  conduct  of  any  nnnnifaoturing 

enterprise   largely   dependent  ? 

2.  Why  does  it  require  as  high  a  degree  of  intelligence  to  produce  a  good 

crop  of  potatoes,  as  in  the  manufacture  of  potato  machinery? 

3.  Why  does  the  mere  statement  that  it  costs  $175.00  to  grow  an  acre  of 

potatoes  mean  so  little? 

4.  How  may  we  arrive  at  a  proper  and   fair  basis   in  the  jjroduction   of 

potatoes  ? 

5.  What  are  the  cost  factors  involved? 

(i    What  items  should  be  charged  against  the  crop  for  labor? 
7.  What  should  be  included  under  materials? 
S.  On  what  should  interest  chai'ges  against  the  crop  be  based? 
!».  What  are  the  legitimate  insurance  charges? 

10.  On  what  should  a  tax  charge  be  levied? 

1 1 .  How   shoiild  depreciation  be   estimated  ? 
]•!    Discuss  overhead  charges. 

l.S.  What  is  meant  by  risk? 

14.  What  charges  should  be   included  under  miscellaneous   items? 
If).  Why  is  it  impossible  to  give  a  set  of  cost  data  which  could  be  regarded 
as  standard  for  the  whole  country? 

16.  Explain  App's  method  of  arriving  at  the  cost  of   producing  potatoes 

on  some  New  Jersey  farms. 

17.  According  to  App's  data,  what  did  it  cost  these  growers  to  produce  a 

bushel  of  potatoes. 


REFERENCES  CITED  165 

IS.  What   was   the   total   production    cost   per   acre,   and   the    net   income 
from   same  ? 

19.  What   was   the   average   price   received   per   barrel   by   these   growers? 

20.  What  was  the  average  labor  income  from  these  farms? 

21.  What  variations   do   the   data    from   different   portions   of   New   York' 

State  show? 

22.  How  do  Steuben  County  data  compare  with  those  of  Nassau  County? 
2:5.  What  is  the  chief  item  of  difference? 

24.  Comi>are   the   per   bushel   cost   in   Steuben   and   Nassau    Counties   and 

explain  reason  why  Nassau  growers  obtained  a  larger  net  income 
per    acre. 

25.  Give    reasons    for    better    showing    made    by    Clinton    and    Franklin 

County  growers  than  by  those  from  other  sections. 

26.  What  correlation   is   shown  by  the  data   between   production   cost   per 

bushel  and  net  profit  per  acre? 

27.  What  is  the  real  determining  factor  governing  net  profit  in  the  data 

presented  ? 

28.  What  would  have  happened  to  the  Nassau  County  growers  had  they 

been  obliged  to  sell  their  crop  for  the  same  price  as  the  Steuben 
County  growers  ? 

29.  What  is  the  chief  lesson  to  be  derived  from  Pelton's  data? 

80.  What    did    the    Milwaukee    hearing    on    potato    production    costs    in 

Wisconsin  in  1920  reveal?     Give  variation  in  cost  of  producing  a 

bushel  of  potatoes. 
.31.  What  were   the   explanations  given   for   the  high   and    low   production 

costs  ? 
.')2.  How  can  we  reduce  production  costs?     What  is  the  urgent   necessity 

for  doing  so? 

QUESTIONS   SUGGESTED  BY   THE  TEXT 

1.  To  what  extent  do  local  growers  make  use  of  the  business  principles 

given  here? 

2.  What  are  the  local  costs  per  acre  and  per  bushel? 

3.  From  the  list  of  cost  factors,  make  a  set  of  questions  that  will  help 

determine  the  cost  per  bushel  on  a  given  farm. 

4.  Use  this  questionary  on  a  few  of  the  leading  farms. 

5.  How  do  these  results  compare  with  those  given  in  this  chapter? 

6.  What  difficulties  are  encountered  in  filling  such  a  questionary? 

References   Cited 

1.  Aw,  F.      1916.     Farm  profits  and  factors  influencing  farm   profits  on 

370  i^otato  farms  in  Monmouth  County,  New  Jersey.     N.  J.  »S'fa. 
liul.  294:    1-103,  April,   1916. 

2.  Fox,  D.  S.     1919.    An  analysis  of  the  costs  of  growing  potatoes.     X.  Y. 

(Cornell)   Hta.  Memoir  22:   553-627,  May,  1919. 

3.  NoBDMAN,  E.     1920.     Cost  and  profit  in  potatoes  to  the  farmer.     Clover- 

land  Mag.  July,  1920:  9 

4.  Pelton,  W.  C.     1918.  Cost  of  potato  production  in   1917.     Ann.   Rat. 

Conn.  Veg.  Gr.  Assn.  April,  1918:   18-23. 


CHAPTER    XTF 

HARVESTING,  PICKING  AND  HANDLING- 
GRADING,  SHIPPING  AND  MARKETING 
THE  POTATO  CROP 

Harvesting  the  Crop. — The  harvesting  of  the  potato  crop  is 
generally  regarded  as  the  most  laborious  process  involved  in  the 
(growing  of  this  most  important  vegetable.  In  some  sections  of 
the  North,  as  in  the  northern  part  of  Maine,  Michigan,  Wisconsin 
and  Minnesota  it  is  also  regarded  as  the  most  critical  operation  of 
the  season,  on  account  of  the  ever-present  possibility  of  unfavorable 
weather,  chiefly  rains,  delaying  the  work  and  tliereby  exposing  the 
crop  to  injury  from  freezing.  The  factors  to  be  considered  in  har- 
vesting the  potato  crop  are:  (1)  Date  of  harvesting;  (2)  imple- 
ments used;  (3)  containers  used;  and  (4)  method  of  handling 
the  crop. 

Date  of  Harvesting. — The  date  of  harvesting  the  potato  crop 
is  very  largely  governed  by  the  character  of  the  crop  and  the 
locality  in  which  it  is  grown.  By  the  character  of  the  crop  is  meant 
whether  it  is  grown  as  an  early  or  a  late  crop.  The  date  is  also 
further  determined  by  the  market  demand  and  the  selling  price. 
For  example,  the  early  truck  crop  of  the  South  is  very  rarely 
allowed  to  reach  full  maturity  before  being  harvested.  Harvesting 
operations  usually  begin  as  soon  as  the  yield  of  marketable  potatoes 
justifies  the  grower  in  sacrificing  yield  for  the  sake  of  securing 
the  higher  price  which  usually  prevails  in  the  early  part  of  the 
season.  On  the  other  hand,  the  late  or  main  crop  of  the  North 
is  usually  allowed  to  remain  in  the  ground  until  the  plants  are 
fully  ripe  or  nntil  the  early  frosts  have  killed  them.  In  short 
crop  seasons,  high  prices  and  an  active  demand  induce  many  a 
grower  of  late  potatoes  to  harvest  his  crop  before  it  is  ripe,  in  order 
to  take  advantage  of  the  prevailing  prices.  It  is  thus  seen  that  the 
date  of  harvesting  does  not  necessarily  represent  any  fixed  stage 
of  maturity  of  the  potato  crop.  As  the  southern  crop  is  only  allowed 
to  reach  maturity,  before  being  harvested,  in  seasons  when  the  price 
is  considered  too  low  to  justify  digging  and  marketing  it,  we  may 
consider  that  the  usual  time  of  harvesting  is  when  the  crop  is  still 
immature,  but  of  sufficient  size  to  give  a  fair  yield.  In  the  North, 
166 


HAND  IMPLEMENTS 


167 


ou  the  other  hand,  the  customary  practice  is  to  allow  the  crop  to 
mature — weather  conditions,  of  course,  permitting. 

Harvesting  Implements  and  Their  Operation. — The  imple- 
ments that  are  used  in  harvesting  the  i)otato  crop  may  he  conveni- 
ently classified  into  two  groups:  (1)  hand  implements;  (3)  horse 
implements. 

Hand  Implements. — The  hand  implements  are  the  ordinary 
hoe;  the  pronged  or  tined  hoe   (Figs.  70  and  71),  spading  fork. 


pstinK  potatoes  in  the  old  fashioned  way.     Hill  selection  is  possible 

wiicii  ihu  Liui^  iB  dug  in  tins  manner. 

six  tined  manure  fork  and  a  specially  constructed  hand  digger, 
with  a  lever  attachment  in  the  rear  which  enables  the  operator  to 
pry  instead  of  lift  the  plant,  with  its  tubers,  out  of  the  soil.  Har- 
vesting a  potato  crop  with  any  of  these  implements  is  a  slow  and 
laborious  process,  and  is  only  practised  where  relatively  small  areas 
are  grown  for  family  use.  In  the  earlier  days,  before  the  develop- 
ment and  perfection  of  the  horse-drawn  digger,  men  became  expert 
in  the  use  of  hand  operated  implements,  and  rather  exceptional 
individual  performances  are  on  record.  Expert  hand  diggers  have 
been  known  to  dig  and  pick  up  100  or  more  bushels  of  potatoes 
in  a  day. 

With  any  of  these  implements,  a  careful  digger  can  harvest  the 
crop  with  a  minimum  amount  of  injury  to  the  tubers;  but  let 


168  HARVESTING  AXD  MARKETING  THE  CROP 

the  same  instruments  be  used  by  a  careless  workman,  and  from  50 
to  15  per  cent  of  the  crop  will  be  injured  in  removing  the  tubers 
from  tlie  soil. 

Horse  Implements  and  Their  Use. — Many  varieties  of  horse 
drawn  implements  are  now  being  used  in  the  harvesting  of  the 
potato  crop.  These  may  be  roughly  divided  into  two  classes :  the 
non-elevator,  and  the  elevator  implements. 

Non-elevator  Implements. — The  first  class  may  be  divided 
into  four  groups:    (1)   the  ordinary  one  or  two-horse  plow;    (2) 


Fig.  71. — Harvesting  potatoes  by   hand    iu   the   tule   lands  near  Stockton,  Calif. 
The  potatoes  are  gathered  as  dug. 

especially  constructed  diggers  with  rigid  finger-like  attachment  to 
sejiarate  the  tubers  from  the  soil  (Fig.  7^2);  (3)  similar  imple- 
ments to  class  2  except  that  the  finger-like  attachment  is  agitated 
by  a  sprocket  wheel,  thus  insuring  a  better  separation  of  the  tubers 
from  the  soil  (Fig.  73)  ;  and  (4)  the  light  drawn  potato  digger, 
with  revolving  fork-like  attachment  in  the  rear,  which  throws  the 
potatoes  and  soil  raised  by  the  shovel  point  to  one  side.  The  sep- 
aration of  the  tubers  from  the  soil  is  supposed  to  be  accomplished 
l)y  this  operation. 

The  Ordinary  Plow. — While  the  one  or  two-horse  plow  cannot 
in  any  sense  be  regarded  as  a  potato  digger,  it  has  been  and  still 
is  a  rather  commonly  employed  implement  in  harvesting  the  early 
or  truck  crop  of  potatoes  in  tlie  Soutli.  The  ])otato  rows  are 
plowed  out  by  turning  as  light  a  furrow  as  possible  without  cut- 
ting tlio  lower  tubers  with  the  jtlow  ])oint   (Fig.  71).     After  the 


POTATO  DIGGERS  169 

potato  plants  are  plowed  out  in  this  manner,  the  furrow  is  gone 
over  by  the  laborers,  usually  women  and  children,  for  the  purpose 
of  removing  the  tubers  from  the  soil  and  throwing  them  into  small 
piles  (Fig.  75).  This  operation  is  commonly  known  as  grabbling 
potatoes.  Usually  the  tubers  from  two  rows  are  thrown  together. 
They  are  then  gathered  into  containers.  This  method  of  harvest- 
ing the  southern  crop  was  quite  generally  practised  throughout  the 
South  prior  to  the  \Yorld  War.  The  scarcity  and  high  price  of 
labor,  as  a  result  of  war  conditions,  virtually  forced  the  southern 
grower  to  adoi)t  the  more  modern  and  labor  saving  elevator  ty])e 
digger.  It  is  questionable  whether,  with  the  return  of  cheaper 
labor,  the  former  methods  of 
liarvesting  the  crop  will  be 
resumed.  In  many  sections 
modern  machinery  will  per- 
manently supplant  the  plow, 
and  thus  eliminate  the  slow 
and  costly  practice  of  grab- 
bling the  potatoes  from  the 

soil.  Fig.  72.— The  Erlipse  dipper  with  ri^ia  nnis 

Tj    ,     ,       TN"  J  to  .separate  the  tubers  from  the  soil. 

Potato  Diggers  2  and  3. —  . 

The  types  of  diggers  given  as  classes  2  and  3  above  are  of  plow-like 
construction  except  that  the  mold-board  is  replaced  by  finger-like 
iron  rods  arranged  like  an  arc  of  a  circle  (Fig.  76).  The  plow  point 
l)asses  directly  beneath  the  plants,  and  the  soil  and  plants  are  forced 
up  over  the  iron  rods.  The  separation  of  the  tubers  is  supposed 
to  take  place  by  the  soil  dropping  through  the  fingers  as  it  is  forced 
back.  Class  2  implements  with  the  rigid  rods  do  not  separate  the 
tubers  from  the  soil  as  completely  and  satisfactorily  as  do  those 
in  class  3.  Either  implement  gives  better  results  in  a  sandy  or  light 
loamy  soil  than  in  a  heavy  one,  or  on  a  dry  rather  than  a  wet  soil. 
They  are  a  desirable  substitute  for  the  ordinary  plow  and,  where 
small  acreages  are  involved  or  where  the  soil  is  full  of  small  stones, 
may  prove  more  satisfactory  than  the  more  expensive  elevator  type 
of  digger.  Im])lements  of  this  type,  when  intelligently  operated, 
will  cause  but  little  injury  to  the  tubers  as  compared  with  the 
elevator  type. 

Potato  Digger  No.  4. — Diggers  of  this  class  are  not  generally 
used  in  the  United  States.  That  they  are  used  is  evident  from  the 
fact  that  they  are  manufactured.  It  is  not  possible  here  to  discuss 
their  merits  or  demerits.     From  the  construction  and  general  ap- 


170  HARVESTING  AND  MARKETING  THE  CROP 

pearaiice  of  the  machine,  (Fig.  7T),  one  can  readily  believe  that, 
in  a  loose  soil,  it  could  be  operated  very  successfully.  It  is  evident 
that  the  tractive  power  required  to  operate  such  a  machine  should 
be  less  than  for  the  heavier  elevator  type  of  digger. 

Elevator  Potato  Diggers, — The  elevator  type  of  potato  digger 
is,  with  but  few  exceptions,  quite  generally  used  in  the  strictly 
commercial  production  centres  of  the  North  and  West,  and  is  grad- 
ually coming  into  general  use  in  the  South.  There  are  many 
makes  of  diggers,  and  each  manufacturer  claims'  special  features 
of  superiority  for  his  particular  machine.  It  is  doubtful  if  one 
would  be  justified  in  naming  any  j)articular  make  of  machine  as 

being  superior  to  all  others. 
There  are,  however,  certain 
outstanding  features  of  dif- 
ference in  construction  which 
may  be  noted.  According  to 
these  differences,  elevator  dig- 
gers may  be  separated  into 
five  classes  as  follows:  (1) 
wheeiUhi„'dt7stare\S?iSrr[h:Xr^Th1  Thosc  with  forward  truck  at- 

two  lead  wheels  straddle  the  row.  tachcd  to  the  pole    (Fig.   78)  ; 

(2)  those  with  truck  attached  to  the  iron  frame  of  the  machine 
(Fig.  79);  (3)  those  with  conveyor,  and  rack  head  (Fig.  78); 
(4)  those  with  a  second  conveyor  in  place  of  rack  head  (Fig.  81) ; 
and  (5)  those  having  a  picker  attachment  (Fig.  78).  There  are 
doubtless  many  other  features  of  difference  which,  while  not  so 
apparent,  might  well  be  considered  as  constituting  a  separate  class 
or  type. 

Operation  of  the  Elevator  Digger. — The  tractive  power  re- 
quired to  operate  the  elevator  type  of  digger  varies  with  the 
character  of  the  soil  and  the  method  of  culture  practised.  In  Aroos- 
took County,  Maine,  where  ridging  is  practised  and  the  soil  for  the 
most  part  is  light  and  porous,  it  is  seldom  that  one  sees  more  than 
two  horses  being  used  to  operate  the  digger  (Fig.  80).  In  the 
Middle  West,  where  level  culture  is  practised,  three  and  four  horses 
are  required  (Fig.  82).  The  same  number  of  horses  are  also  neces- 
sary in  the  irrigated  sections  of  the  West. 

To  leave  the  impression  that  the  elevator  digger  can  only  be 
operated  by  horses  would  be  misleading,  because  the  tractor  is  now 
being  quite  freely  used  in  some  sections  to  haul  the  digger,  and  its 


SUCCESSFUL  OPERATION  OF  POTATO  DIGGER 


171 


further  use  for  this  purpose  is  almost  certain  to  increase.  The 
caterpillar  type  of  tractor  seems  to  be  well  adapted  to  this  purpose, 
(Fig.  83),  thougli  possibly  it  would  hardly  be  justifiable  to  claim 
that  it  was  actually  superior  to  other  makes.  Within  the  past  few 
years,  elevator  digger  manufacturers  have  added  a  gasoline  engine 
to  the  equipment  of  some  of  their  diggers  (Figs.  78  and  ?!)).     The 


.tK^.'.* 


Fig.  74. — Plowing  out  tiie  [xitato  crop  with  it  turniii'-' i)luw,  A  coiiinion  nietliod  of 
harvesting  potatoes  in  the  South. 

engine  is  mounted  over  the  conveyor  and  is  designed  to  operate  the 
conveyor,  kicker  and  rear  rack  vine  and  tuljer  separator.  This 
relieves  the  horses  of  the  tractive  power  required  to  operate  these 
several  parts,  which,  in  the  absence  of  the  gasoline  engine,  are 
operated  by  being  geared  to  the  wheels  of  the  digger.  With  the 
gasoline  engine  functioning  properly,  the  horses  have  only  to  exert 
the  necessary  power  to  haul  the  machine,  and  at  the  same  time  force 
its  shovel  point  beneath  the  potato  tubers  and  push  soil  and 
tubers  on  the  conveyor. 

The  successful  operation  of  a  potato  digger  involves  several 
points,  the  careful  observance  of  which  will  guarantee  the  removal 
of  the  crop  with  a  minimum  amount  of  mechanically  injured 
tubers.     The  operator  has  much  to  do  with  the  efficiency  of  any 


172 


HAR\'ESTIXCJ  AND  MAliKKTIXO  TlIK  C^ROr 


make  of  machine  as  regards  the  ])er  cent  of  injured  tubers  and  the 
thoroughness  of  the  Avork  in  general.  This  may  be  illustrated  by 
mention  of  the  following  point.  The  shovel  point  of  the  digger 
should  be  so  adjusted  as  to  go  deep  enough  to  avoid  cutting  the 
tubers.  It  is  almost  equally  important,  on  the  other  hand,  to 
not  go  any  dee])er  than  is  necessary,  so  as  to  avoid  increasing  the 
drauglit,  as  well   as  tlic  overtaxing  of  the  conveyor.  os])ecially  if 


(    1    IMi^        I    tl  \    H  1  tubci^  after  the  row  liii>  I...  I,  |,I,.u,,l  Mill  with  a 

V  labuuuLi^   Hi  I  1  ilhn  n)^ll>  operation 

the  soil  is  heavy  or  a  little  wet.  The  clogging  of  the  conveyor  is 
a  source  of  annoyance  to  the  operator  and  a  direct  loss  of  time  to  the 
owner.  In  light  soils  and  where  the  vines  have  thoroughly  ripened, 
it  is  sometimes  a  good  plan  to  go  somewhat  deeper  than  is  necessary 
in  order  to  prevent  undue  injury  to  the  tubers  1)y  the  soil  sifting 
through  the  conveyor  chain  too  quickly,  thus  permitting  the  tubers 
to  travel  over  a  large  portion  of  the  bare  conveyor.  By  attention 
to  this  detail,  and  the  removal  of  a  portion  or  all  of  the  conveyor 
agitators,  much  surface  injury  may  be  avoided.     Another  prolific 


SUCCESSFUL  OPERATION  OF  POTATO  DIGGER 


173 


source  of  injury  is  that  of  driving  the  machine  too  fast.  This  often 
causes  an  unnecessary  amount  of  agitation.  The  author  has  per- 
sonally observed  four  diggers  at  work  in  a  potato  field  on  sandy 
soil,  where  the  horses  were  frequently  allowed  to  break  into  a  slow 
trot.  At  such  times,  the  potato  tubers  Avould  frequently  bound 
from  the  conveyor  to  a  height  of  eighteen  inches  or  more. 

In  heavy  soils  and  wliere  the  vines  are  heavy,  fast  driving  seems 
to  lessen  the  amount  of  clogging;  consequently,  the  operator  is  often 


Fig.  70. — Digger  with  typical  shovel  point  and  arc-formed  tines,  and  two  guide 
wheels  in  front. 

tempted  to  drive  faster  than  is  necessary.  When  the  digger  is 
equipped  with  a  gasoline  engine  it  is  possible  to  drive  slower;  since 
the  speed  at  which  the  conveyor  moves  can  be  regulated  at  will 
by  the  operator.  Mechanical  injury  of  the  tubers  may  be  still 
further  lessened  by  lowering  the  rear  rack  or  conveyor,  as  the 
case  may  be,  to  a  ])oint  where  the  drop  of  the  tubers  from  the 
digger  to  the  ground  will  be  so  slight  as  to  cause  little,  if  any, 
injury  (Fig.  84). 

When  properly  adjusted,  the  elevator  type  of  digger  should 
deliver  the  vines  at  one  side  of  the  row  and  the  tubers  in  the 
centre.  Some  makes  of  machines  do  this  more  effectively  than 
others,    chiefly    on    account    of    a    slightly    different    arrangement 


174  HARVESTING  AND  M.UIKETIXG  TPIE  CROP 

and  curve  of  the  vine  aud  tuber  rear  rack  rods.  A  machine  oper- 
ated at  au  even  rate  of  speed  will  always  do  more  effective  work 
than  when  jerky  or  varying  speed  movements  are  permitted. 

Under  favorable  conditions,  the  elevator  digger  will  dig  from 
three  to  four  acres  per  day. 

Picking  and  Handling  the  Tubers. — In  different  sections  of 


Fig.  77. — A  light  draught  potato  digger  with  revolving  fork-like  attachment  in  the 
rear,  which  throws  the  potatoes  and  soil  to  one  side  of  the  row. 

the  country,  varying  practices  prevail  in  regard  to  the  picking  aud 
handling  of  the  newly  dug  tubers.  The  early  crop  in  the  South, 
for  example,  is  generally  graded  as  it  is  picked,  and  is  at  once 
put  into  the  containers  in  which  it  is  to  be  shipped  to  market. 
When  the  weather  is  hot,  the  potatoes  should  be  gathered  as  quickly 
as  possible  after  they  are  dug,  as  they  are  easily  injured  by  the 
hot  sun.  In  very  warm  weather,  the  more  careful  and  experienced 
southern  growers  aim  to  dig  in  the  late  afternoon,  leaving  many 


PICKING  AND  HANDLING  THE  TUBERS 


175 


lying  on  the  ground  over  night  to  be  gatliered  early  in  the  morning 
when  they  are  well  cooled  oil'.  It  is  always  advisable  to  liaul  the 
crop  out  of  the  field  as  soon  as  convenient  after  it  has  been  sacked 
or  barrelled. 

The  soiitherri  grower  uses  baskets,  buckets,  hampers  and  crates 
in  picking  up  potatoes  (Figs.  90  and  91). 

In  Maine,  the  potatoes  are  usually  gathered  into  splint  baskets 
with  a  strong  wooden  bale  (Fig.  84).  The  tubers  are  transferred 
from  the  basket  to  the  barrel  and  in  general  the  transfer  is  not  made 


U>^ 


Fig.  78. — Combined  potato  digger  and  picker. 


in  as  gentle  a  manner  as  could  1)e  desired.  The  quick  dumping  of 
a  basket  of  potatoes  into  an  empty  barrel  inevitably  injures  the 
surface  of  many  of  the  tubers.  Much  injury  could  be  avoided  by 
tipping  the  barrel,  when  emptying  the  first  two  or  three  baskets; 
or  by  lowering  the  basket  into  the  barrel  before  emptying  it.  They 
are  hauled  in  the  unheaded  barrel  from  the  field  to  the  shipping 
station  or  the  home  storage  house  as  the  case  may  be  (Fig.  84). 

In  New  Jersey,  some  of  the  early  crop  is  gathered  into  five- 
eighth  bushel  splint  baskets  (Fig.  85),  in  which  they  are  hauled 
direct  to  market,  or  to  the  sizer  if  they  are  to  be  graded  and 
shipped  in  sacks.  The  American  Giant  Crop  of  Monmouth  County, 
New  Jersey,  is  gathered  into  baskets  from  whence  it  is  emptied 
into  sacks.  This  crop,  like  the  early  Irish  Cobbler  crop,  is  gen- 
erally hauled  direct  from  the  field  to  the  shipping  station.  The 
grading  is  done  by  the  pickers  as  they  gather  the  crop,  or  the 
tubers  are  run  over  a  sizer  in  the  field  or  loading  station. 


176 


HAR^T^STINO  AND  MARKETING  THE  CROP 


///  Wc.slcni  iVr//'  Yuii<\  ami  in  some  sections  of  the  ]\Iiddk;  West, 
the  potato  cro]i  is  ^i;ath('i'(Ml  into  wooden  Ijoxes  or  crates  holding 
a  hushel  (Fig.  .Sii),  in  which  tliey  aic  liauled  I'rom  the  lield  to  the 
storage  house,  cellar,  or  shi[)i)ing  station.  In  the  West,  and  in 
some  sections  of  the  South,  a  large  part  of  the  crop  is  gathered  in 
wire  baskets  by  .the  pickers,  and  transferred  to  two  bushel  sacks 
if  the  crop  is  to  be  stored.     If  it  is  Ijeing  niai'keted  as  dug  it  is 


Fig.  79. — By  the  aid  of  the  gasoline  eiiuiiie  to  operate  the  eonveyor  belt,  vino  kifker  and 
vine  and  tuber  separating  rod  racks,  the  traction  necessary  to  haul  the  digger  is  reduced  to  a 
point  where  two  horses  can  easily  handle  it.  Note  low  position  of  tuber  rod  rack.  When 
lowered  in  this  manner  the  drop  is  so  slight  that  it  does  not  injure  the  tubers.  Courtesy 
of  Bateman  Mfg.  Co. 

usually  graded  in  the  field  (Fig.  85).  Careful  growers  cover  tlie 
inside  of  the  wire  basket  with  burlap  to  prevent  tuber  injury. 
When  stored  on  the  farm,  the  pickers  empty  three  half-bushel 
baskets  into  each  sack.  The  sacks  are  hauled  to  the  storage  house 
without  being  tied,  and  are  emptied  directly  into  tlie  storage  bin. 

In  ihe  tide  lands  of  the  Stockton,  California  district,  where  it 
is  claimed  the  digger  cannot  be  successfully  operated,  the  crop  is 
dug  by  hand.  Each  workman  has  his  own  basket  and  gathers 
the  tubers  as  he  digs  them. 


GRADING 


177 


Cost  of  Picking  Potatoes. — The  wages  ])ai(l  to  potato  pickers 
have  advanced  so  rapidly  (hiring  the  past  few  years  that  it  is 
difficult  to  give  accurate  cost  data  on  the  gathering  of  the  potato 
crop.  In  Aroostook  County,  Maine,  prior  to  1914,  it  was  custom- 
ary for  the  grower  to  pay  })ickers  from  G  to  8  cents  a  harrel 
and  board.  Day  lielp  received  from  $3.00  to  $3.50  per  day  and 
board  in  the  early  part  of  tlie 
digging  season,  and  from  $3.50 
to  $3.00  toward  its  close.  The 
prices  paid  in  the  same  locality 
in  1930  Avere  from  15  to  IG 
cents  a  barrel  and  board,  or  1 7 
to  18  cents  without  board.  Day 
lal)or  started  at  $5.00  ]ier  day 
and  board,  and  wound  np  at 
$6.00  to  $7.00  per  day.  Expert 
Maine  potato  pickers,  when  the 
yield  is  good,  have  been  known 
to  pick  as  liigh  as  135  barrels 
in  a  day.  A  few  men,  under 
favorable  conditions,  will  aver- 
age 100  or  more  barrels.  The 
average  picker  will  pick  about 
GO  barrels  per  day. 

In  the  Red  Eiver  Valley, 
pre-war  prices  were  about  four 
cents  a  bushel. 

In   the   Norfolk,  Virginia,       r.o.  so -Thiseievat-.,  ,„.,,  ,.i„, „..,„. <ss- 
section,  10  cents  a  barrel  was   fuiiy  operated  by  two  hoi.sc^«ith,.utti.p  aid  ot  a 

.  .  frasolme  engine.  In  this  picture  we  have  a  good 

considered    a    good    price    prior    view  of  the  vine  and  tuber  separating  rod  lack. 

to  1914,  but  in  1930,  30  cents  was  demanded  for  the  same  service. 
Grading. — Potato  grading  has  received  more  attention  during 
the  past  three  or  four  years  (1917-31)  than  at  any  previous  time 
in  the  history  of  the  potato  iirdustry  of  this  country.  The  primary 
cause  of  this  increased  interest  was  a  ruling,  made  by  the  United 
States  Pood  Administration  during  the  season  of  1917-18,  com- 
pelling the  large  handlers  of  ])otatoes  to  grade  them  according 
to  certain  prescribed  standards,  formulated  by  the  Bureau  of  Mar- 
kets of  the  United  States  Department  of  Agriculture.  Without 
attempting  to  go  into  the  details  involved  in  this  first  effort  on 


178 


HARVESTING  AND  MARKETING  THE  CROP 


the  part  of  the  government  to  enforce  the  grading  of  potatoes, 
it  may  suffice  to  say  that  the  objections  to  the  potato  grade  rules 
on  the  part  of  the  growers  have  been  hirgely  overcome ;  and  in  the 
section  where  the  bitterest  opposition  to  grading  developed,  we 
now  find  the  growers  heartily  in  favor  of  it.  While  the  recog- 
nition of  the  merits  of  a  uniform  and  standard  grade  of  potatoes 


Fig.  81. — A  potato  digger  with  rear  conveyor  belt.  Such  a  machine  does  not  separate 
the  vines  from  the  tubers.    Greeley,  Col. 

was  rather  slow,  it  is  believed  that  the  majority  of  the  growers 
are  now  heartily  in  favor  of  the  movement. 

Grades. — -The  most  recent  grade  requirements,  promulgated 
by  Truax  ■*  of  the  Bureau  of  Markets,  provide  for  three  grades, 
viz.:  U.  S.  Grade  Fancy,  U.  S.  Grade  No.  1,  and  U.  S.  Grade 
No.  2.     The  requirements  of  these  grades  are  as  follows : 


"U.  S.  Grade  Fancy. — This  grade  shall  consist  of  sound  potatoes 
of  one  variety  which  are  mature,  bright,  smooth,  well  shaped,  free  from 
dirt  or  other  foreign  matter,  frost,  injury,  sunburn,  second  growth,  growtii 
cracks,  cuts,  scab,  blight,  soft  rot,  dry  rot,  and  damage  caused  by  disease, 
insects,  or  by  mechanical  or  other  means.  The  range  in  size  shall  be 
stated  in  terms  of  minumum  and  maximum  diameter  or  weight  following 


GRADING 


179 


the  grade  name,*  but  in  no  case  shall  the  diameter  be  less  tlian  two  inches. 
"In  order  to  allow  for  variations  incident  to  commercial  grading  and 
handling,  five  per  centum  by  weight  of  any  lot  may  vary  from  the  range 
in  size  stated,  and,  in  addition,  three  per  centum  by  weight  of  any  such 
lot  may  be  below  the  remaining  requirements  of  this  grade;  but  not  more 
than  one-third  of  such  three  per  centum,  that  is  to  say,  not  more  than 


Fig.  82. — A  four-mule  team  operates  one  digger  while  two  horses  and  a  gasoline  engine 
operate  the  other. 

one  per  centum  by  weight  of  the  entire  lot.  may  have  the  flesh  injured 
by  soft  rot. 

"U.  S.  Grade  No.  i. — This  grade  shall  consist  of  sound  potatoes  of 
similar  varietal  characteristics  which  are  practically  free  from  dirt  or 
other  foreign  matter,  frost  injury,  sunburn,  second  growth,  growth  cracks, 
cuts,  scab,  blight,  soft  rot,  dry  rot,  and  damage  caused  by  disease,  insects, 
or  mechanical  or  other  means. 

"The  diameter  of  the  potatoes  of  the  round  varieties  shall  not  be  less 
than  one  and  seven-eighth  inches,  and  of  potatoes  of  long  varieties  one 
and  three-fourth  inches. 

"In  order  to  allow  for  variations  incident  to  commercial  grading  and 
handling,  five  per  centum  by  weight  of  any  lot  may  be  under  the  prescribed 
*  Such  statements  as  the  following  will  be  considered  as  meeting  this 
requirement:  "U.  S.  Grade  Fancy,  2  to  3  inches;"  "U.  S.  Grade  Fancy, 
10  to  16  oz. ;"  "U.  S.  Grade  Fancy,  2  inches  and  larger;"  "U.  S.  Grade 
Fancy,  10  oz.  and  larger." 


180 


llAliVESTlXG  AND  MAKKETLXG  THE  CROP 


size.  and.  in  addition,  six  per  ccntiini  by  wcijilit  of  any  such  lot  may  be 
below  the  remaining-  requirements  of  tliis  grade;  but  liot  more  than  one- 
third  of  sueh  six  per  t-entum.  that  is  to  say.  not  more  than  two  per 
centum  by  weight  of  tlie  entire  lot.  may  have  the  flesh  injured  by  soft  rot. 
"U.  S.  Grade  No.  2. — This  grade  shall  consist  of  potatoes  of  similar 
varietal  characteristics,  which  are  practically  free  from  frost  injury  and 
soft  rot.  and  which  arc  free  from  serious  damage  caused  by  sunburn,  cuts, 
scab,  blight,  dry  rut.  or  other  disease,  in.sects.  or  mechanical  or  other  means. 
"The  diameter  of  ])otatoes  of  this  grade  shall  not  be  less  than  one  and 
one-half  inches. 


Fig.  S3. — Tho  potato  digger  oan  he  suf  ce.^.sf  ally  operated  by  a  tnictor.    Presque  Isle,  Mo. 

"In  order  to  allow  for  variations  incident  to  commercial  grading  and 
handling,  five  per  centum  hj  weight  of  any  lot  may  be  under  the  prescribed 
size,  and,  in  addition,  six  per  centum  by  Aveight  of  any  such  lot  may  be 
below  the  remaining  requirements  of  this  grade;  but  not  more  than  one- 
third  of  such  six  per  centum,  that  is  to  say,  not  more  than  two  per  centum 
by  weight  of  the  entiie  lot.  may  have  the  flesh  injured  by  soft  rot. 

"Definition  of  Grade  Terms. — As  used  in  these  grades: 

'•■Mature'  means  that  the  outer  skin  {epidermis)  does  not  loosen 
or  'feather'  readily  during  the  ordinary  methods  of  handling. 

"  'Bright'  means"  free  from  dirt  or  other  foreign  matter,  damage  or 
discoloration  from  any  cause,  to  an  extent  such  that  the  outer  skin 
(epidermis) has  the  attractive  color  normal  for  the  variety. 

"  'Smooth'  means  free  from  second-growth,  growth  cracks,  and  other 
abnormally  rough  surfaces. 

"  'Well  shaped'  means  the  normal,  typical  shape  for  the  variety  in 
the  district  where  grown,  and  free  from  pointed,  dumb-bell  shaped, 
excessively  elongated,  and  other  ill-formed  potatoes. 

•"Free'  means  that  neither  the  appearance  nor  the  physical  structure 
has  been  appreciably  damaged  by  the  causes  mentioned. 


ORADTNO 


181 


182 


HARVESTING  AND  MARKETING  THE  CROP 


"  'Diameter'  means  the  greatest  dimension  at  right  angles  to  the  longi- 
tudinal axis. 

"'Soft  rot'  means  a  soft  mushy  cnndition  of  the  tissues  from  what- 
ever cause. 

"  'Practically  free'  means  that  the  appearance  shall  not  be  injured  to 
an  extent  readily  a{)parent  upon  casual  e.xamination  of  the  lot,  and  that  any 
damage  from  the  causes  mentioned  can  be  removed  by  the  ordinary  process 
of  paring  without  appreciable  increase  in   waste  over   that    which    would 


Fig.  S.5. — Grading  potatoes  with  a  belt  grader  Bridgoton,  X.  J.  Potatoes  gathered 
into  I  bushel  splint  baskets,  in  which  they  are  hauled  to  the  bizer.  Courtesy  of  MLnch 
Bros.  Bridgeton,  N.J. 

occur  if  the  potato  were  perfect.     Loss  of  outer   skin    (epidermis)    only 
shall  not  be  considered  as  an   injury  to  the  appearance. 

"  'Free  from  serious  damage'  means  that  any  damage  from  the  causes 
mentioned  can  be  removed  by  the  ordinary  processes  of  paring  without 
increase  in  waste  of  more  than  ten  per  centum  by  weight  over  that  which 
would  occur  if  the  potato  were  perfect." 

Potato  Grading  and  Mechanical  Sizers. — The  importance  of 
properly  grading  potatoes  before  shij^inng  them  to  market  cannot 
be  too  strongly  emphasized.  The  place  to  grade  them  is  on  the 
farm,  or  at  shipping  point,  if  proper  facilities  are  not  available 
on  the  farm.  The  old  custom  of  shipping  ungraded  stock  is 
being  gradually  abandoned,  as  the  grower  comes  to  realize  the  folly 


MECHANICAL  SIZERS  183 

of  expecting  the  large  commission  merchant,  or  the  distributor  at 
terminal  receiving  points  to  perform  this  service  at  his  own  expense. 
The  realization  that  he  pays  for  this  service,  and  that  such  service 
is  infinitely  more  expensive  in  the  city  than  on  the  farm  or  at 
shipping  point,  and  that,  in  addition,  he  pays  the  freight  on  the 
stock  that  the  distributor  culls  out  is  rapidly  converting  the  grower 
to  the  idea  of  home  grading.     Well  graded  stock,  put  up  in  attrac- 


FiG.  86. — A  potato  harvesting  scene  on  the  farm  of  T.  E.  Martin,  West  Rush,  N.  Y. 
In  this  section  of  New  York  State  it  is  a  common  practice  to  gather  the  potatoes  in  bushel 
boxes.    By  courtesy  of  T.  E.  Martin. 

tive  containers,  will  always  sell  at  a  premium  over  ordinary  stock, 
and  will  pay  many  times  over  for  the  slight  cost  involved  in  grad- 
ing the  stock.  Ungraded  stock  usually  sells  on  the  basis  of  the 
poorest  material  in  it,  rather  than  on  its  average  quality. 

Method  of  Grading. — While  it  is  possible  to  hand-grade  pota- 
toes, it  is  not  so  economical  of  time  as  is  desirable  where  large 
quantities  of  potatoes  have  to  be  handled.  The  use  of  the  mechani- 
cal sizer  greatly  facilitates  the  work  of  grading. 

Mechanical  Sizers. — Although  there  are  many  makes  of  me- 
chanical sizers,  or,  as  they  are  designated  by  the  manufacturers, 
potato  graders,  on  the  market  at  the  present  time,  they  can  all  be 
broadly  separated  into  three  classes,  viz.,  those  with  sizing  belt 
conveyor,  operated  by  a  crank  turned  by  hand,  or  by  i^ulley  con- 


184 


HARVESTING  AND  MARKETING  THE  CROP 


iiected  with  a  gasoline  engine  or  electric  motor  (Figs.  85  and  87)  ; 
those  in  which  the  screen  is  suspended  between  the  wooden  or 
steel  frame  of  the  sizing  machine  (Fig.  89);  and  small  hand 
screens  resting  on  a  stand  (Figs.  90  and  91). 

The  sizing  machine,  when  properl}^  operated,  removes  all  the 
undersized  potatoes,  as  Avell  as  the  loose  dirt  collected  with  the 
tnhors  in  picking  them  uj).     The  first  ty])e  of  machine  is  usually 


Fir,.  S7. — Sizing  potatoes  with  a  large  power-driven  sizer  having  a  capacity  of  over  100 
barrels  per  hour.  The  potatoes  are  hauled  from  the  field  to  the  sizer  in  slat  crates.  On  the 
G.  W.  Waller  farm,  Hastings,  Fla. 

constructed  with  two  l)elts,  the  one  with  the  smaller  sized  meshes 
operating  within  the  other.  This  gives  two  grades  of  potatoes, 
No.  1  and  No.  2,  and  the  culls.  Some  of  the  larger  nnichiiies, 
constructed  chiefly  for  use  on  the  early  crop  in  the  South,  are 
])rovided  with  three  belts,  which  give  three  sizes,  I's,  2's  and  3's. 

The  second  type  of  sizer  seems  to  be  almost  wholly  a  western 
product,  where  it  is  used  almost  to  the  entire  exclusion  of  the  first 
type.  This  type  of  sizer  is  operated  by  the  workman  doing  the 
grading  by  rocking  or  shuffling  it  back  and  forth.  The  only 
reason  that  can  be  suggested  for  this  apparent  regional  preference 
is  that  the  belt  conveyor  type  is  of  later  origin,  and  has  not  as  yet 


MECHANICAL  SIZiaiS 


185 


generally  invaded  western  territory.  In  our  opinion,  the  belt  con- 
veyor type  of  sizer  possesses  some  points  of  advantage  over  the 
western  type,  in  that,  if  properly  operated,  it  should  not  skin  and 
bruise  the  tubers  as  much  as  the  other.  The  jolting  back  and 
forth  of  the  tubers  on  the  sizing  screen,  as  the  potatoes  roll  for- 
ward, is  much  more  likely  to  skin  and  bruise  them  than  will  its 
even  movement  over  the  belt  conveyor.  A  simpler  type  of  sizer 
is  quite  generally  used  in  Texas  and  adjacent  states.  It  consists 
in  some  localities  of  what  might  be  regarded  as  an  ordinary  old- 


Fiu.  S8. — A  Laiidy  laboi-saving  device  for  removing  the  barrels  of  tized  potatoes  from 
the  sizer.  Note  small  trucks  operating  on  wooden  tracks.  By  having  two  tracks  with  a  truck 
on  each  there  is  no  interruption  in  the  operation  of  the  sizer.  On  the  G.  W.  Waller  farm, 
Hastings,  Fla. 

time  circular  hand  screen,  the  bottom  of  which  is  covered  by  a 
heavy  wire  screen  with  one  and  three-fourth  inch  meshes.  This 
screen  is  placed  on  a  specially  constructed  wooden  stand  with  bag 
attaclunents  (Fig.  90).  The  potatoes  are  dumped  into  the  screen 
as  gathered  and  briskly  shuffled  back  and  forth  until  all  the  dirt 
and  small  potatoes  have  been  shaken  through,  after  which  the  re- 
maining tubers  are  dumped  through  an  opening  in  the  stand  into 
a  sack  attached  beneath  it.  In  the  Brownsville  district,  in  southern 
Texas,  an  oblong  hand  screen  is  used  (Fig.  91).  While  this  is  a 
more  or  less  primitive  method,  as  compared  with  the  mechanical 


186 


HARVESTING  AND  MARKETING  THE  CROP 


sizer,  it  serves  the  purpose  and  is  so  cheap  that  the  grower  can 
own  a  sufficient  number  to  distribute  along  the  entire  length  of  any 
of  his  fields,  thus  having  them  convenient  to  the  pickers  in  any 
portion  of  the  field. 

In  Maine,  the  growers,  as  a  general  rule,  use  what  is  known  as 
a  rack  or  sorting  table  (Fig.  92)  when  grading  potatoes.  This 
table  is  usually  of  home   construction,   and  is  simply  used  as  a 


Fig.  89. — The  western  type  of  potato  sizer  mounted  on  sled  runners  to  permit  of  haul- 
ing it  with  a  horse  or  horses. 

convenient  method  of  hand  sorting  and  sacking  or  barrelling  the 
stock.  All  unmerchantable  stock  is  supposed  to  be  removed  as  the 
potatoes  roll  do\vn  into  the  sack  or  barrel.  When  the  grading 
or  "racking,"  as  it  is  usually  called,  is  done,  after  the  potatoes  are 
stored  they  are  generally  shovelled  onto  the  rack,  but  when  the 
stock  is  racked  from  barrelled  material  a  board,  cut  to  fit  the  lower 
opening  of  the  sorting  table,  is  used  to  ])revent  the  potatoes  from 
rolling  out  when  the  barrel  is  emptied  at  the  upper  end.  Skilled 
workmen  can  sort  and  grade  potatoes  quite  rapidly  by  the  aid  of 
such  a  sorting  table,  and,  where  reasonable  intelligence  and  care 


GRADING  FOR  A  FANCY  TRADE 


187 


are  exercised,  material  will  conform  to  United  States  grade 
requirements.  The  ojjen  slat  bottom  of  the  sorting  table  serves 
to  dispose  of  all  refuse  and  the  very  small  potatoes  that  may 
be  in  the  stock.    The  sorting  table  is  never  used  in  the  field. 

Grading  for  a  Fancy  Trade. — Here  and  there  may  be  found 
the  beginnings  of  an  attempt,  usually  on  the  part  of  dealers, 
to  develop  a  select  market  for  a  uniform  sized  tuber  put  up  in  a 
special  package.     As  yet,  the  bushel  box  seems  to  be  the  favorite 


tei 


Ki^;,  '.»ii, — Type  of  hand-sizing  screen  and  stand  used  intheEagle  Lake  districtin  Texas. 

container.  Smooth  uninjured  tubers  are  selected  and  wrapped 
in  a  light  wrapping  paper  and  carefully  packed  in  containers. 
In  one  instance  that  has  attracted  attention,  a  light  brown  wrap- 
ping paper  was  used  and  each  wrapper  was  sealed  with  sealing 
wax.  The  seal  used  gave  the  name  of  the  firm  putting  them 
up  (Fig.  93).  They  were  packed  in  a  50  pound  container  and  sold 
for  about  $3.00  per  box  when  ordinary  stock  was  selling  at  about 
$1.00  per  hundredweight.  The  selected  tubers  averaged  about  nine 
ounces  in  weight. 

A  few  years  ago,  a  New  York  firm  was  observed  that  had  devel- 
oped quite  a  volume  of  business  in  supplying  high  class  hotels 
and  restaurants  with  special  sizes  of  potatoes  for  baking,  boiling, 
and  frying.     The  bakers  averaged  nine  to  ten  ounces  and  each 


188  HAR\T5STIXG  AND  MARKETIXCJ  THE  CROP 

liihcr  was  wrapped.     TliP   ]iric<'   rccoivcd    was   around   four   cents 
per  tuljer. 

It  has  long  been  an  opinion  tluit  the  development  of  a  special 
trade  for  fancy  graded  potatoes  was  a  peri'ectly  leasible  i)roposition 
for  those  in  a  position  to  furnish  a  continuous  supply.  The  idea 
is  that  there  is  a  necessit}'  for  the  marketing  of  well  graded  pota- 
toes in  small  packages  that  the  retailer  can  sell  direct  to  the  con- 
sumer without  l)reaking  the  package.     Potato  tubers  can  be  sepa- 


rated witliout  mucli  tr()ul)l(>  into  sizes,  running  from  .")  to  4,  4  to 
G,  G  to  8,  8  to  10,  10  to  1'3,  etc.,  ounces  and  ])ut  in  heavy  pai)er 
carton  packages  of  10,  15,  and  20  or  more  pounds  in  weight 
(Fig.  94).  Heavy  manila  paper  bags  may  be  sul)stituted  for  the 
carton  boxes.  The  housewife  who  desired  boiling  potatoes  could 
make  use  of  either  of  the  first  two  sizes.  If  bakers  were  desired, 
tlie  G  to  8,  or  8  to  10  ounce  tuber  sizes  would  be  found  to  meet 
lier  requirements.  The  larger  sizes  Avould  be  found  more  economi- 
cal for  frying,  potato  chips,  etc.  The  advantage  of  having  potatoes 
of  a  certain  size  is  that  they  "wall  all  cook  in  about  the  same  time, 
and  with  a  little  experience,  the  time  required  to  cook  a  given 
size  can  be  quite  accurately  determined.     These  are  some  of  the 


INJURY  TO  TUBERS  IN  GRADING 


189 


advantages  from  llie  housewife's  standpoint;  but  a  number  of 
others  might  W  giv<'n,  such  as  the  advantage  and  convenience  to 
the  retailor  of  li;iii<lliiig  potatoes  in  unbroken  packages;  the  eli- 
mination of  waste;  tlie  guarantee  tliat  each  package  contaius 
sound  tubers  of  n  given  size;  and  Iliuilly,  the  quality  of  the  potato 
does  not  deteriorate  by  being  exposed  to  light,  as  it  ordinarily 
does  when  haiuUed  in  bulk  by  the  retailer. 

The  successful  development  of  such  an  enteri)riso  i-;  largely 
dependent  u])on  the  willingness  of  the  consumer  to  ])iiy  a  siillicieut; 
premium  over  ordinary  stock  to  make 
it  ])rolita])le  to  grade  the  potatoes  and 
])ut  them  lip  in  the  manner  described. 
►Service  of  this  sort  cannot  be  rendered 
unless  it  is  amply  reimbursed.  It  is 
l)elieved  that  the  well-to-do  consumer 
is  willing  to  pay  the  price,  provided 
he  gets  the  quality  demanded.  With 
the  question  of  remuneration  settled. 
I  lie  furtlier  and  continued  success  of 
the  enterprise  is  wliolly  dependent 
upon  tlie  grower  or  the  dealer  actually 
engaged  in  the  grading  and  putting 
up  of  the  material.  As  long  as  he 
performs  this  task  in  an  lioiu'st 
manner,  and  is  able  to  furnisli  tlie 
retailer  with  a  steady  supply  throughout  the  season,  he  nury  expect 
a  constantly  increasing  demand  for  his  product. 

Large  establishments,  such  as  mail  order  groi-ers  and  others, 
have  expressed  a  willingness  to  handle  potatoes  put  up  in  small 
jiackages,  provided  they  could  l)e  assured  of  a  steady  supply. 

Injury  to  Tubers  in  Picking  and  Grading. — Some  mention 
has  l)een  jn-eviously  made  as  to  injury  to  the  tubers  occasioned 
by  the  rocking  and  belt  conveyor  types  of  graders,  but  no  special 
emphasis  was  laid  upon  the  necessity  of  exercising  the  utmost  care 
in  this  matter.  In  the  case  of  the  early  crop  of  the  South,  wdiich 
is  usually  harvested  when  immature,  it  is  very  necessary  to  handle 
it  ^nth  as  much  care  as  possi])le  to  avoid  skinning  and  bruising 
the  tubers.  It  is  quite  important  to  reduce  the  handling  of  the 
potatoes  to  a  minimum,  and,  for  this  reason,  many  of  the  best 
growers  still  prefer  to  have  the  pickers  grade  the  stock  into  No.  I's 


Viu.  02.— Sorting  table  or  rack 
by  Maine  growers. 


190 


HARVESTING  AND  MARKETING  THE  CROP 


and  2's  as  it  is  gathered.  In  this  ^vay  the  potatoes  receive  the 
minimum  of  handling,  as  they  are  transferred  to  harrels  or  sacks 
directly  from  the  rece])tacles  in  Avhich  they  are  gathered.  In  the 
Hastings  district  in  Florida,  it  is  quite  a  common  jiractice  to  use 


Fig.  93. — A  box  of  select  baking  potatoes  wrapped  in  a  light  but  tough  bru\\  ii  wrapping 
paper  with  free  end  fastened  to  wrapper  with  sealing  wax  stamped  with  the  firm's  name. 

collapsible  slat  crates  in  picking  up  the  potatoes.  The  filled  crates 
are  hauled  to  the  grader  where  they  are  sized,  graded  and  bar- 
relled (Fig.  87).  Where  the  sizing  machine  follows  the  pickers 
in  the  field,  there  is  also  a  minimum  amount  of  handling.  Much 
injury  can  be  avoided  by  the  exercise  of  care  in  emptying  the 
basket  or  crate  of  potatoes  on  the  grader,  and  in  the  reduction 
of  all  unnecessary  height  of  drop  from  the  grader  into  the  container, 


INJURY  TO  TUBERS  IN  GRADING 


191 


gj 


S5: 


<  a 

El 


Sir 


II 


6| 


192 


1 1 Al{ VESTING  AND  MAKKETIXG  THE  CROP 


111  wliuli  thrv  arc  to  l.c  slii|i|.,.,l  to  market.  :\[(".-]iaiiic-al  injuries 
may  Itc  still  further  reduced  where  macliine  sizers  are  used,  es- 
l)ecially  when  they  are  oi)erated  by  gasoline  engine  or  electric 
motor,  by  operatijig  the  convenor  belt  at  a  moderate  rate  oC  speed. 
When  the  tubers,  through  a  too  rapid  movement  of  the  belt  con- 
veyor, are  forcibly  discharged  from  the  spouts  of  tiie  sizer  and 
allowed  to  drop  to  the  bottom  of  a  barrel,  it  is  inevitable  tliat  many 

more  bruises  and  cuts  will 
result  from  this  method  of 
Iiandling  than  when  a 
moderate  speed  is  allowed, 
and  a  piece  of  canvas  or 
gunny  sack  is  used  to  break 
the  fall  of  the  tuber  into 
the  barrel.  The  application 
of  common-sense  methods 
of  handling  the  jiotato  crop 
will  do  much  toward  less- 
ening the  l)ruising  and  cut- 
ting of  the  tul)ers,  and  will 
•■ii^  materially  improve  their 
"•»*•■■-.,  appearance  on  arrival  at 
destination  ]ioiut. 

Fio.  9"). — Hauling  empty  barrels  to  potato  field  QViit->'>-»i no-     onr?     ■|Vr^rL-o+ 

near  Oaley,  Va.     Note  size  of  load,  also  that  the.v  are  snipping    anO    MaFKet- 

all  stave  barrels.     Few  if  any  splint  barrels  are  used    'mg; The       '>hil)Dino'       aild 

ill  the  Eastern  Shore  district.  &'         _             ^      11       n 

marketing  of  potatoes  in 
a  successful  and  businesslike  manner  calls  for  an  entirely  different 
kind  of  experience  or  ability  from  that  possessed  by  the  average 
grower.  Some  of  the  best  potato  growers  are  a  sad  failure 
when  it  comes  to  the  business  end  of  slii|)])ing  and  salesmanship. 
It  should  be  borne  in  mind,  too,  that  when  distant  markets  have 
to  be  sought  in  the  disposal  of  the  crop  it  is  often  impossible  or 
impracticable  for  the  grower  to  dispose  of  his  own  crop,  unless  he 
is  fortunate  enough  to  have  selected  a  good  commission  house 
to  which  he  can  consign  it.  There  is  still  another  factor  involved 
in  the  marketing  of  an  individual's  crop,  especially  for  the  south- 
ern truck  grower,  who  must  always  ship  to  a  distant  market,  and 
that  is  that,  unless  he  is  a  large  grower,  he  is  unable  to  load  a  car 
inside  of  twenty-four  hours  as  it  is  usually  desirable  to  do. 

Containers. — The  first  consideration  in  the  shijiping  and  mar- 


CONTAINERS 


193 


ketiiig  of  the  crop  is  the  container  in  which  it  is  to  he  packed 
for  shipment.  As  the  appearance  of  the  package  or  container  has 
much  to  do  with  the  successful  marketing  of  the  crop  it  is  important 
that  the  potatoes  be  put  up  in  clean  and  attractive  containers. 
The  types  of  containers  used  the  country  over  in  marketing  pota- 
toes named  in  the  order  of  their  widest  use  are  the  burlap  sack 
of  100,  120,  150  and  165  pounds  capacity;  stave  and  splint 
barrels,  with  burlap  cover  (Figs.  95  to  100)  ;  the  double-headed 
stave  barrel;  the  hamper  of  varying  » 
capacity  usually  50  pounds;  and  the 
five-eighth  bushel  peach  basket  (Fig. 
101).  Large  quantities  of  northern 
grown  stock,  especially  in  the  early 
autumn,  are  marketed  in  bulk. 

The  double-headed  barrel  is,  so  far  ||v^ 
as  the  writer  is  informed,  used  only  in 
Florida,  and  most  largely  in  the  Hast- 
ings district.  When  well  ventilated 
double-headed  barrels  are  properly 
filled  with  bright,  well-graded  stock, 
headed  and  neatly  stencilled,  they 
present  the  most  attractive  appear- 
ance of  any  potato  container  used, 
(Figs.  87  and  88) ;  and,  when  opened,        Fig-  96.— The  Beaufort  s.c.  type 

,1  ,     ,  1  11         1         J       •     •  of  splint  barrel  with  inner  set  of  hoops 

tne     potatoes     snow     the     least     injury  which  impart  a  considerable  degree  of 
from  handling.  rigidity  to  the  barrel. 

Two  reasons  might  be  advanced  for  the  double-headed  barrel 
not  being  more  generally  used  by  southern  truck  growers,  the  first 
being  the  cost,  and  the  second,  the  additional  labor  involved  in  head- 
ing the  barrels.  Prior  to  the  war,  the  double-headed  barrel  cost 
the  grower  in  the  neighborhood  of  36  cents.  In  1918  they  cost 
from  70  to  85  cents,  and  were  not  oljtainable  in  suiBcient  quantity 
to  meet  the  demands.  The  pre-war  price  for  splint  barrels  was 
18  cents,  and  22  to  24  for  the  stave  barrel. 

The  use  of  new  burlap  sacls  with  an  attractive  brand  (Fig. 
102)  gives  a  more  presentable  appearance  to  the  package;  and 
the  stock  usually  sells  at  a  sufficient  premium  above  the  average 
to  pay  the  grower  handsomely  for  his  additional  investment. 

One  of  the  crying  needs  of  the  day  is  a  standard  size  of  sack. 
All   things  considered,   the  two-bushel   or   120-pound   sack   comes 


lU 


HARVESTING  AND  MARKETING  THE  CROP 


nearest  to  being  the  ideal  size.  It  makes  a  neat  and  attractive 
package  if  properly  filled  and  sewed  up,  and  is  not  so  heavy  as  to 
be  lunneldy.  The  150-  and  165-pound  sacks  are  rather  heavy  to 
handle,  and  are  more  apt  to  become  slack  in  handling.     A  properly 

filled  sack  should  be  so  firm, 
-wlien  sewed  up,  as  to  handle 
like  a  stick  of  cordwood. 
Such  a  package  will  show 
k"~s  tuber  injury  from  hand- 
ling than  will  be  found  in  a 
^lack  package. 

A  further  objection  to 
the  use  of  various  sizes  of 
.^.icks  is  the  confusion  it 
tauses  in  the  minds  of  those 
\v  h  o  a  1 1  e  m  p  t  to  keep 
informed  on  the  market 
quotations.  Unless  one  is 
familiar  with  the  practices 
in  vogue  in  different  sec- 
tions, one  cannot  be  certain 
w  liether  the  price  given  is 
lor  a  two,  two  and  one-half, 
or  two  and  three-quarter 
bushel  sack  unless  it  is 
specifically  stated  in  the 
report. 

The  liamper  is  chiefly 
used  in  southern  Florida  and  in  southern  Texas.  Just  why  the 
hamper  is  the  container  most  favored  in  these  sections  is  rather 
difficult  to  answer.  The  five-sixth  bushel  hamper  and  the  half- 
barrel  hamper  being  almost  universally  used  in  these  sections  for 
the  shipment  of  string  beans,  green  peas  and  other  truck  crops, 
the  grower  has  become  accustomed  to  handling  them  (Fig.  101). 
The  high  price  received  for  the  new  potatoes  is  also  a  very  impor- 
tant factor  to  be  considered.  The  sum  of  $5.00  or  $(5.00  for  a 
50-pound  hamper  of  potatoes  does  not  seem  so  staggering  to  the 
consumer  as  would  $10.50  to  $19.80  a  barrel. 

The  five-eiglilh  husltel  hasJcet  used  by  some  New  Jersey  growers 
in  marketing  their  early  crop  of  Irish  Coblilers  is  employed  only 
where  nearby  markets  are  to  be  supplied.  (Fig.  85.) 


Fiii.  97.— A  \vell-«iaded  and  u.ll-lillfd  barrel 
of  potatoes  ready  to  Ije  covered  with  burlap  top. 
This  stave  barrel  is  properly  ventilated. 


SHIPPING  POTATOES 


195 


Shipping  Potatoes. — The  shipping  of  potatoes  to  distant  mar- 
kets involves  some  knowledge  of  the  proper  loading  of  the  car  or 
the  boat  in  which  the  shipment  is  to  be  placed.  The  question  of 
the  proper  method  of  loading  cars,  and  the  type  of  car  best  suited 
for  the  purpose  has  been  quite 
thoroughly  discussed  by  More  and 
Borland,^  Bird  and  Grimes/  and 
Grimes.-  As  a  result  of  these  men's 
studies  and  the  information  they 
have  published  on  the  subject,  there 
has  been  a  very  considerable 
decrease  in  the  losses  sustained 
through  overheating  in  late  spring 
and  summer  shipments,  and  from 
frosting  during  cold  periods  in  the 
Winter.  The  proper  way  to  load 
a  car  with  barrels  is  to  lay  the 
barrels  on  their  sides;  begin  the 
first  layer  of  barrels  at  one  end  of 
the  car,  placing  the  first  against 
the  side  of  the  car,  while  the  next 
two  are  placed  end  to  end  to  eadi 
other.  The  second  tier  should  In 
staggered  with  the  first  (Fig.  103). 
It  is  not  advisable  to  place  more         i  >  ■  '^*^-   ii't^^  t^p  Loop  is  removed 

,-  .,  ..  /.ii.n         fr""'   t''C  barrtl  then  the  burlap  cover  is 

than    three    tiers    Ot    barrels    m    the    spread  over  and    the   hoop  pressed  down 

SI     J.  ,1  1  .         into  place  over  the  burlap  and  well  nailed, 

ummer  or  hot  weather  ship- 
ments will  not  permit  of  as  heavy  loading  as  can  be  safely  practised 
during  the  cooler  autumn  and  winter  weather. 

The  burlap-covered  barrel  cannot  be  safely  loaded  on  its  side 
or  bilge,  as  the  upper  end  of  the  barrel  would  not  sustain  the  weight 
of  two  or  more  barrels  on  top  of  it.  Such  containers  carry  best 
by  standing  the  first  tier  of  barrels  on  their  ends,  and  placing 
one  tier  of  barrels  on  their  sides  upon  tlie  first  tier  as  it  is  being 
placed  (Fig.  104). 

In  the  summer  shipment  of  potatoes  in  sacks,  it  is  not  ad- 
visable to  pile  them  in  solid  tiers  as  is  done  in  fall  and  winter 
shipments.  Grimes  recommends  (I.e.  p.  13)  "the  placing  of  the  first 
sack  on  end  in  one  corner  of  the  car  with  the  flat  side  of  the  sack 
leaning  against  the  side  of  the  car."  He  further  says:  "Make 
13 


196 


HMl VESTING  AND  MARKETING  THE  CROP 


'■m 


sure  that  the  bottom  of  the  sack  is  at  least  G  inches  from  the 
side  of  the  car.  Lean  two  more  sacks  against  the  first.  On  top 
of  these  three  sacks  place  one  sack  flat,  taking  care  to  keep  one 
end  at  least  10  inches  from  the  side  of  the  car,  and  the  other  end 
well  on  top  of  the  upright  sack  nearest  the  centre  line.  Another 
sack  should  be  placed  flat  on  top  of  this,  but  with  one  end  tight 
against  the  side  of  the  car.  The  manner  in  which  these  two  flat 
sacks  are  loaded  is  very  important;  if  they  are  not  correctly  and 
securely  placed,  the  load  is  practically 
jV^  ^d|H^H^H||fl  certain  to  shift  in  transit.  The  same 
^^  ^^I^^^^^^^H  ^y^^^^^  <^^'  placing  the  sacks  is  followed 
^HbmB^4^^^^^^H  on  the  opposite  side  of  the  car.  This 
^^^^■^ >^L  ^^^^^1  leaves  a  narrow  centre  aisle  through 
^^^HL1|^  ^%  ^I^^H  ^^^e  whole  length  of  the  car,  insuring 
■PJPPWJ^^^^*    -ood  ventilation  (Fig.  105). 

In  the  shipment  of  sacked  j)otatoes 
during  cool  weather  an  entirely  dif- 
ferent S3^stem  of  loading  is  practised. 
Bird  and  Grimes^  suggest  laying  the 
sacks  lengthwise  of  the  car.  The  first 
TOW  of  sacks  is  laid  about  a  foot  or  so 
from  the  end  of  the  car;  the  second 
icr  should  extend  a  little  further  back ; 
uiid  the  succeeding  tiers  should  be  piled 
likewise  (Fig.  lOfi).  The  car  should 
be  similarly  loaded  from  the  other  end. 
The  object  should  be  to  so  load  the  car 
as  to  prevent  shifting  of  the  load  in  transit,  and,  at  the  same 
time,  make  provisions  for  a  free  circulation  of  air  around  the  load. 
In  severe,  cold  weather,  the  area  in  the  centre  of  the  car  should  be  left 
unfilled,  thus  permitting  the  use  of  a  heater  stove.  The  car  should 
not  be  filled  clear  to  the  top.  It  is  desirable  to  leave  at  least 
a  foot  of  space,  and  in  large  cars  18  inches  is  preferable. 

Hampers  do  not  make  satisfactory  packages  for  shipment  on 
account  of  their  frailty.  When  loaded  four  tiers  high,  the  lower 
tier  of  packages  is  quite  apt  to  arrive  at  destination  in  a  badly 
broken  condition.  Hampers  should  be  tiered  bottom  to  bottom  or 
top  to  top  as  the  case  may  be ;  by  alternating  the  order  of  placement 
of  the  first  tier,  it  is  possible  to  effect  a  considerable  economy  in 
space,  and  at  the  same  time  increase  the  solidity  of  the  load.    The 


Fig.  99. — A  splint  barrel  being 
covered.  Note  light  construction  of 
barrel. 


SHIPPING  POTATOES 


197 


railroads  dislike  to  carry  hamper  shipments  of  potatoes,  because 
they  almost  invariably  have  claims  presented  for  injury  sustained 
during  transit. 

Warm  weather  shipments  should  invariably  be  made  in  ven- 
tilated cars  (Fig.  105).  The  ordinary  box  car  should  never  be  used,, 
unless  slat  doors  are  provided. 

During  the  cooler  autumn  weather,  the  box  car  is  entirely 
acceptable  as  long  as  there  is  no  likelihood  of  a  low  drop  in  tem- 
perature. As  soon  as  severe,  freezing 
weather  may  be  expected,  it  is  unsafe 
to  use  a  box  car  except  for  very  short 
hauls.  When  shipments  are  made  to 
distant  i^oints  during  severely  cold 
weather  or,  when  the  car  in  transit 
is  likely  to  pass  through  areas  where 
low  temperatures  prevail,  the  ship- 
ment should  be  made  in  refrigerator 
cars;  or  in  a  special  t3'pe  of  car 
provided  with  a  heater,  such  as  the 
Eastman  heater  car  which,  as  far  as 
it  is  available,  is  used  in  the  move- 
ment of  potatoes  from  Maine  points. 
Unfortunately,  the  supply  of  refrig- 
erator and  heater  cars  is  utterly 
inadequate  for  the  movement  of  the 
potato  crop  to  market  during  the 
winter,  making  it  necessary  to  use  the  ordinary  box  car.  In  order 
to  use  box  cars  the  shipper  is  obliged  to  go  to  the  expense  of  lining 
them  with  building  paper,  and  constructing  wooden  false  floors, 
walls  and  ends  (Fig.  106).  Full  particulars  concerning  the  conver- 
sion of  a  box  car  into  a  fairly  good  substitute  for  a  refrigerator  car 
are  given  by  Bird  and  Grimes.^ 

A  few  favored  localities  in  the  South  are  able  to  avail  them- 
selves of  water  transportation  in  moving  their  crop  to  market. 
The  most  notable  example  in  this  respect  is  that  of  the  Norfolk, 
Virginia,  district  where  a  large  proportion  of  the  New  York,  Boston, 
Baltimore,  and  Wasliington  consignments  are  shipped  by  boat 
rather  than  by  rail.  (Figs.  107  and  108).  The  advantage  of  boat 
over  rail  shipment  is  that  the  shipper  can  be  absolutely  certain 


The  hoop  in  place  ready 


198 


HARVESTING  AND  MARKETING  THE  CROP 


of  the  date  of  arrival  of  his  consignment  when  he  moves  it  by  boat, 
while  by  rail  he  has  no  assurance  when  his  potatoes  will  reach 
market.     New  York  sliipments  by  boat  arrive  within  24  hours 


Fig.  102. — In  the  Ft.  Gibson,  Okla.,  district,  potatoes  are  graded  and  sackedin  the  field 
and  are  hauled  in  springless  waffons  to  the  shipping  station.  The  grower  of  this  stock 
marks  his  sacks  with  a  wheel  brand.     Courtesy  of  W.  n.  Olin. 

of  their  departure  from  Norfolk,  and  Boston  shipments  within  36 
hours;  whereas  rail  shipments  may  take  several  days  if  not  a  week 
or  more,  de])ending  upon  freight  congestion  in  terminal  yards. 
Marketing. — The  successful  marketing  of  potatoes  offers  many 


MARKETING  199 

difficulties,  particularly  in  the  disposal  of  the  early  or  truck  crop 
which,  on  account  of  its  perishable  nature  and  the  comparatively 
short  period  in  which  it  must  be  handled,  necessitates  quick  action 
on  the  part  of  the  grower  or  dealer.  The  development  of  com- 
mercial growing  centres  is,  in  part,  the  outcome  of  a  growing 
recognition  of  the  advantages  derived  from  having  a  large  output 
to  dispose  of  at  a  given  shipping  point.  If  the  crop  volume  is  large 
enough,  it  attracts  buyers  from  all  the  large  northern  and  middle- 


FlG.  103.— Proper  way  to  load  douole-headed  barrels  to  insure  an  even  distribution  of 
weight.  _  Loaded  in  this  manner,  the  bulk  of  weight  on  upper  layers  is  supported  by  heads  of 
barrels  in  lower  tier.    Courtesy,  Bureau  of  Markets,  U.  S.  Dept.  Agr. 

western  sections  of  the  country,  with  the  result  that,  when  the 
market  demand  for  new  potatoes  is  brisk,  there  is  keen  competition 
between  representatives  of  different  commission  firms  as  to  who 
will  secure  the  largest  quantity  of  the  best  stock.  This  competition 
insures  good  prices  to  the  grower,  and  relieves  him  of  the  more  or 
less  onerous  task  of  attempting  to  market  his  own  crop.  Another 
advantage  is  that  the  crop  is  given  a  much  wider  distribution  than 
it  could  have  possibly  received  had  the  growers  themselves  at- 
tempted to  dispose  of  it  in  distant  markets. 

In  some  sections  the  growers  have  their  own  selling  organiza- 
tion, and  in  some  cases  these  have  been  wonderfully  successful. 
One  of  the  largest  and  most  successful  of  these  marketing  organiza- 


200 


HMIVESTING  AND  MARKETING  THE  CROP 


tions  is  the  Eastern  Shore  of  Virginia  Produce  Exchange  located 
at  Onle}',  Virginia. 

The  disposal  of  the  new  crop  becomes  difficult  and  uncertain 
as  to  returns  when  terminal  distributing  points  become  glutted 
through  an  oversupply  and  an  inactive  demand  on  the  part  of  the 
retail  trade  and  the  consuming  public.    Under  these   conditions 

it  often  becomes  necessary  to 
roll  the  stock  unsold ;  the  usual 
practice  being  to  consign  it  to 
some  commission  house.  Fre- 
quently cars  are  diverted  en 
route,  in  order  to  take  advan- 
tage of  a  stronger  market  in 
some  other  city  than  the  one 
to  which  the  car  was  originally 
billed. 

In  the  marketing  of  the 
late  crop  of  potatoes  the  grower 
or  dealer  has  a  longer  season 
of  operation,  and  is  not  dealing 
with  such  a  perishal)le  product, 
as  the  crop  is  usually  mature 
and  the  weather  cool.  The 
element  of  risk  in  shi})ping  late 
potatoes  is  that  of  being  frosted 
while  en  route  to  destination, 
or  of  a  portion  of  the  shipment 
being  injured  by  overheating 
AvheiJ  a  stove  is  used  in  the  car. 
The  method  of  disposal  of  the  crop  is  so  similar  as  to  require 
no  further  discussion. 

When  Should  a  Grower  Sell? — The  proper  time  at  which  to 
dispose  of  his  crop  is  a  question  wdiich  is  often  difficult  for  the 
grower  to  decide.  Each  grower  should  keep  himself  informed  as 
to  the  probable  extent  of  the  crop,  through  the  monthly  reports 
of  the  Bureau  of  Crop  Estimates  of  the  United  States  Department 
of  Agriculture  and  all  other  available  sources.  Whenever  it  be- 
comes apparent  that  a  crop  in  excess  of  375  million  bushels  is  going 
to  be  harvested,  it  is  a  fairly  safe  assumption  that  prices  will  not 
reach  a  very  high  level,  unless  there  is  a  shortage  of  other  food 


Fio.  104. — Proper  way  to  load  burlap- 
covered  stave  barrels.  Courtesy  of  Bureau  of 
Markets,  U.  S.  Dept.  Agr. 


WHEN  SHOULD  A  GROWER  SELL 


201 


crops,  such  as  wheat,  corn  and  other  products.  When  no  such 
shortage  exists  and  a  large  crop  is  in  sight,  it  is  usually  advisable 
to  sell  the  crop   as   harvested,   provided  the   price   at  that   time 


Fig.  lOo. — Approved  method  of  loading  sacks  of  potatoes  for  summer  shipment.    This 
insures  good  ventilation.   Courtesy  of  the  Bureau  of  Markets,  U.  S.  Dept.  Agr. 

affords  a  reasonable  return  on  the  investment  involved  in  its  pro- 
duction. There  are  seasons  when  it  may  be  advisable  to  sell  the 
crop  from  the  field  at  a  price  which  barely  covers  the  actual  cost 


Fig.  106. — Approved  method  of  loadins  sacked  potatoes  for  winter  shipment.  Note 
false  floor  and  ends.  This  method  of  loading  insures  an  even  and  uninterrupted  circulation 
of  air.     Courtesy  of  the  Bureau  of  Markets,  U.  S.  Dept.  Agr. 

of  production,  and  thereby  avoid  the  extra  cost  of  storing  and  re- 
handling  the  crop  later  in  the  season,  with  a  fair  prospect  of  not 
receiving  any  more  for  it  at  that  time  than  when  harvested.     It 


202 


HARVESTING  AND  MARKETING  THE  CROP 


is,  of  course,  apparent  that  if  everyone  followed  this  advice  it  would 
result  in  a  complete  slump  in  prices.  In  fact,  it  would  be  a  physical 
impossibility  for  the  railroads  to  move  the  entire  late  crop  of  po- 
tatoes during  the  harvest  period;  and  even  if  this  were  possible, 
there  is  enough  storage  to  take  care  of  only  about  one-third  of  the 
crop.  It  thus  becomes  evident  that  at  least  two-thirds  of  the  late 
crop  must  he  stored  on  the  farm,  to  await  distribution  throughout 
the  late  fall,  winter  and  early  spring  months. 


:,k3«5^-v/>'- 


Fig.  107.— Hauling  the  crop  to  shipping 


the  Norfolk  district. 


On  the  other  hand,  when  a  short  crop  is  apparent  it  would  not 
be  a  good  plan  for  every  grower  to  hold  on  to  his  whole  crop  in 
the  expectation  of  receiving  a  high  price  in  the  spring.  The  result 
would  be  that  prices  throughout  the  early  part  of  the  winter  season 
would  be  forced  to  such  an  extremely  high  figure  that  the  con- 
sumption of  potatoes  would  be  very  materially  curtailed,  with  the 
probability  that,  Avhen  the  grower  got  ready  to  dispose  of  his  crop, 
he  would  find  the  market  overstocked,  and  the  consuming  public's 
taste  diverted  to  other  starchy  food  substitutes.  Under  such  con- 
ditions, the  price  received  for  the  crop  might  be  very  much  below 
what  it  should  be  as  judged  by  the  season's  supply.     Good  stable 


WHEN  SHOULD  A  GROWER  SELL 


203 


prices  and  market  conditions  can  only  be  expected  when  there  is 
a  steady  flow  of  potatoes  to  the  distributing  centres,  thus  preventing 
wide  price  fluctuations,  and  insuring  a  maximum  consumption. 

Every  commercial  late  croj)  potato  grower  should  aim  to  provide 
sufficient  storage  space  on  his  own  farm  to  enable  him  to  store  his 
Avhole  crop,  if  need  be.  When  provided  with  the  necessary  facili- 
ties for  taking  care  of  his  crop,  he  is  not  o])liged  to  dispose  of 


Fig.  108. — Boats  from  truck  farms  awaiting  their  turn  to  unload  at  the  Old  Dominion 
docks,  Norfolk,  Va.     An  ideal  method  of  conveying  the  crop  to  shipping  point. 

it  at  harvesting  time  if  the  prices  being  paid  are  ruinously  low. 
On  the  other  hand,  if  a  satisfactory  price  is  being  offered,  it  is 
often  justifiable  to  dispose  of  the  whole  crop,  even  though  ample 
provision  for  storage  is  at  hand.  The  ideal  method  of  marketing 
the  crop  would  be  for  each  grower  to  dispose  of  a  sufficient  portion 
of  his  crop  to  take  care  of  the  needs  of  the  trade.  It  goes  without 
saying,  of  course,  that  such  an  ideal  will  never  be  reached,  as  there 
Avill  always  be  those  who,  through  lack  of  storage  facilities,  are 
obliged  to  sell  their  crop  as  harvested. 


204  HARVESTING  AND  MARKETING  THE  CROP 

Stabilization  of  prices  for  farm  products,  and  potatoes  in  })ar- 
ticular,  can  only  be  accomplished  through  an  effective  and  compre- 
hensive growers'  organization  for  the  purpose  of  pooling  crops  and 
selling  them  through  some  central  selling  agency.  Whether  such 
a  millenium  in  the  marketing  of  potatoes  will  ever  be  reached  is 
difficult  to  say.  The  present  trend  of  thought  and  action  is  in 
that  direction.  This  is  evidenced  by  the  recent  formation  of  a 
number  of  strong  farmers'  cooperative  organizations. 

QUESTIONS    ON    THE   TEXT 

1.  What  are  tlie   chief  factors   involved   in   harvesting   the   potato  crop? 

2.  What   fixed   period   in   the   growth    of   the   crop   do   the   data   of   har- 

vesting represent? 

3.  What  determines  the  date  of  havesting? 

4.  How  do  the  southern  and  nortliern  dates  differ? 

f).  What  two  general  classes  of  harvesting  implements  are  used? 
G.  Name  the  hand  implements  that  may  be  used. 

7.  Name  and  describe  the  non-elevator  types  of  diggers. 

8.  How  is  tlie  ordinary  plow  used  ? 

9.  How  do  potato  diggers  2  and  3  operate? 

10.  How   docs   class   4    implement   differ    from   2    and    3    in    its    operation? 

11.  What  can  you  say  of  the  number  of  types  of  elevator  potato  diggers? 

12.  What    are    some  "of    the    outstanding    features    of    difference    in    their 

construction  ? 

13.  Why  are  four  horses  necessary  to  operate  them   in  some  sections  and 

not  in   others? 

14.  Describe  the  gasoline  equipped  digger.     What  is  the  function  of   the 

gasoline  engine  in  the  operation  of  the  digger? 

15.  How    may    the    cutting    and    bruising    of    the    tubers    by    diggers    be 

minimized  ? 
If).  How  does  fast  driving  increase  the  amount  of  tuber  injury? 

17.  How  important  is  it  to  lower  the  rear  rack  or  conveyor  belt?     Why? 

18.  How    do    practices    differ    in    different    sections    of    the    country    with 

respect  to  picking  and  handling  the  tubers? 

19.  Describe  the  IMaine  method  of  picking  and  handling  the  crop. 

20.  Describe   the  New   Jersey   method   of  picking  and   handling   the   crop. 

21.  HoAV  does  western  New  York  handle  the  crop? 

22.  In  the  West  and  in  some  sections  of  the  South  how  is  the  crop  usually 

gathered  ? 

23.  What   is   the   practice   in   the   tule   lands   of   the    Stockton,    California, 

district? 

24.  What  is  the  cost  of  picking  potatoes? 

25.  What  impetus  did  potato  grading  receive  during  the  war? 

26.  What  can  you  say  of  its  probable  permanency? 

27.  Describe  the  grades  advocated  by  the  U.  S.  Department  of  Agriculture. 

28.  (^f  what  importance  is  it  to  the  grower  to  have  his  potatoes  properly 

graded  ? 


QUESTIONS  ON  THE  TEXT  205 

29.  Dcbcribe  the  operation  of  the  belt  conveyor  type  of  sizer. 

30.  Describe  the  operation  of  the  western  type  of  sizer. 

31.  Describe  the  hand  screen  or  sizer  and  tell  how  it  is  operated. 

32.  What  do  the  Maine  growers  use  as  an  aid  in  the  operation  of  grading 

potatoes?     Is  it  in  any  sense  a  sizer? 

33.  Discuss  grading  for  a  fancy  trade. 

34.  What  are  the  sizes  of  tubers  suggested? 

35.  What  are  some  of  the  advantages  of  having  potatoes   separated   into 

uniform  sizes? 

36.  Of  what  advantage  would  it  be  to  the  retailer  to  handle  potatoes  in 

small  packages? 

37.  Of  v/hat  advantage  to  the  consumer  from  the  quality  standpoint? 

38.  Is  the  average  grower  ordinarily  able  to  successfully  market  his  crop? 

Give  reasons. 
30.  What  kinds  of  containers  are  used   in   shipping  the   crop    to   market? 

40.  Describe  and  explain  the  respective  merits  of  each  container  and  reasons 

for  its  use. 

41.  What  are  the  chief  oljjections  to  large  sacks? 

42.  What  trouble  is  caused  from  the  use  of  sacks  of  varying  capacities? 

43.  What  objection  is  there  to  the  use  of  the  hamper?     Where  used? 

44.  How  should  double-headed  stave  barrels  be  loaded  in  a  car?' 

45.  Should  burlap-covered   barrels   be   loaded   in   the   same   manner   as   the 

double-headed  barrels?     Why? 

46.  How  should  summer  shipments  in  sacks  be  loaded?     What  type  of  car? 

47.  How  does  autumn  or  winter  loading  of  cars  differ  from  summer  loading? 

48.  How  may  box  cars  be  made  suitable  for  use  in  cold  weather? 

49.  What  are   some  of   the  difficulties   involved   in   the   marketing   of   the 

early  or  truck  crop? 

50.  How  has  the  development   of   large  commercial  production   centres  in- 

fluenced the  marketing  problem? 

51.  Why    is   the   marketing   of   the   late   crop    of   potatoes    a    less    difficult 

problem  ? 

52.  How  is  the  grower  to  determine  when  it  is  the  proper  time  to  sell? 

53.  To  what  extent  is  the  railroad  a  limiting  factor? 

54.  Why  should  the  commercial  grower  make  provision  for  the  storage  of 

his  crop? 

55.  What  would  be  the  ideal  method  of  marketing  the  crop? 

56.  How  may  the  price  of  potatoes  be  stabilized? 

57.  What  is  the  present  trend  of  thought  in  this  direction? 

QUESTIONS   SUGGESTED  BY  THE  TEXT 

1.  At  what  stage  of  growth  do  the  local  growers  harvest  their  potatoes? 

2.  List  the  methods  of  harvesting  used  locally,  in  order  of  popularity. 

3.  Which  methods  are  least  injurious  to  the  tubers? 

4.  Describe  local  methods  of  picking  and  handling  potatoes. 

5.  From  local  growers  ascertain  the  cost  of  picking  potatoes. 

6.  What  grading  and  sizing  is  done  locally?     Give  methods. 

7.  Describe  local  methods  of  shipping  and  marketing. 

8.  What  containers  are  used? 


206     ■         HARVESTING  AND  MARKETING  THE  CROP 
References   Cited 

1.  Bird,  H.  S.,  and  A.  M.  Grimes.     1918.    Lining  and  loading  cars  of  pota- 

toes for  protection  from  cold.     U.  8.  Dept.  Agr.  Bur.  Mkts.  Doc. 
17:   1-26.     Oct.,  1918. 

2.  Grimes,  A.   M.      1919.     Handling  and   loading  southern   new  potatoes. 

U.  8.  Dept.  Agr.  Farmers'  Bui.  1050:   1-18,  May,  1919. 

3.  Moke,  C.  T.,  and  C.  R.  Borland.     1910.     Commercial  handling,  grading 

and  marketing  of  potatoes.     U.  S.  Dept.  Agr.  Farmers'  Bui.  753: 
1-40,  Nov.  1,  1916. 

4.  Tbuax,  H.  E.     1920.     United  States  grades  for  potatoes.     U.  S.  Dept. 

Agr.  Bur.  Mkts.  Circ.  96:  1-4,  May,  1920. 


CHAPTER  XIII 

POTATO  STORAGE  AND  STORAGE  SHRINKAGE 

As  the  agricultural  and  economic  importance  of  perishable 
food  products  increases  in  any  given  community,  state  or  country, 
the  question  of  storage  at  once  enters  into  the  problem  of  their 
conservation  and  distribution  throughout  the  period  in  which  these 
crops  are  not  normally  produced. 

The  relative  ease  with  which  the  potato  can  be  held  in  storage 
during  the  winter  months  in  the  northern  section  of  the  United 
States  and  Canada,  or,  under  similar  climatic  conditions,  in  other 
])ortions  of  the  world,  has  not  served  to  stimulate  any  very  careful 
study  looking  toward  the  determination  of  the  optimum  storage 
conditions  for  this  crop.  In  view  of  the  fact  that  the  quantity 
of  potatoes  annually  stored  for  winter  and  spring  use  is  relatively 
large,  it  would  seem  that  we  should  know  more  than  we  now  do 
about  the  actual  shrinkage  that  is  likely  to  occur  under  certain 
conditions  during  a  given  storage  period. 

Object  of  Storage. — The  primary  object  in  the  storage  of 
any  product  is  that  of  prolonging  its  edible  stage  of  maturity 
throughout  a  longer  period  of  time.  The  secondary,  though  by 
no  means  unimportant,  object  of  storage  is  that  of  minimizing  the 
losses  occurring  during  the  storage  period.  The  chief  sources 
of  shrinkage  in  storage  result  from  moisture  losses  and  decay 
Storage  makes  it  possible  to  hold  over  the  late  or  main  crop  of 
potatoes  in  the  North  throughout  the  winter  and  spring  months, 
thereby  enabling  the  grower  or  the  dealer  to  dispose  of  the  crop 
at  such  times  as  the  requirements  of  the  market  demand,  and  by 
so  doing  avoid  marketing  it  when  there  is  an  over-supply  and  con- 
sequently low  prices. 

The  successful  storage  of  potatoes  is  dependent  upon  a  number 
of  factors  among  which  may  be  mentioned  temperature,  humidity, 
aeration,  exclusion  of  light,  soundness  of  tubers  stored,  freedom 
from  dirt  and  moisture,  and,  last  but  not  least,  size  of  the  pile. 

Storage  Temperature. — There  are  many  current  notions  re- 
garding the  best  temperature  at  which  to  store  potatoes,  but  until 
quite  recently  there  have  been  few  experimental  data  upon  which 

207 


208  POTATO  STORAGE  AND  SHRINKAGE 

to  base  conclusions.    This  has  boon   particuhirly  true  witli  respect 
to  seed  stock. 

The  following  opinions  are  given  with  a  view  of  ])resenting  such 
information  as  we  have- at  the  present  time.  Cooper^  recommends 
a  temperature  of  from  33  to  35  degrees  F.  as  about  right  for 
potatoes.  Fraser,"  in  discussing  ventilation  and  temperature,  says 
"The  potato  must  be  kept  cool,  al)out  33  degrees  l^eing  a  favorable 
temperature."  Corbett*  recommends  a  temperature  of  34  degrees 
as  a  minimum  and  45  degrees  as  a  maximum  throughout  tiie  entire 
storage  period.  Grubb  and  Gilford"  believe  that  in  winter  the 
temperature  of  the  potato  storage  house  should  be  kept  as  near 
32  degrees  as  possible.  In  this  connection  they  say,  "It  is  best 
when  it  does  not  go  below  30  degrees  nor  above  36  degrees." 
Wright  and  Castle, '^^  in  their  discussion  of  storage,  mention  the 
investigations  of  Dr.  Parisot,  a  French  scientist  who,  as  a  result 
of  his  studies,  recommended  46  degrees  as  the  ideal  storage  tem- 
perature for  potatoes  in  winter.  Appleman^  found  in  some  recent 
investigations  that  ordinarily  the  freezing  temperature  of  the  pota- 
to lies  between  28  and  26  degrees.  Some  years  ago  the  writer, 
while  conducting  potato  investigations  at  the  Vermont  Station, 
used  a  basement  cellar  for  storage  purposes  in  which  the  tempera- 
ture on  a  number  of  occasions  dropped  to  30  degrees  and  on  one 
occasion  went  as  low  as  28  degrees.  Aside  from  a  rather  tardy 
germination  of  the  seed  when  planted,  no  ill  effects  were  noted  from 
these  low  temperatures.  Since  1911,  a  considerable  portion  of  the 
seed  potatoes  produced  by  the  Office  of  Horticultural  and  Pomo- 
logical  Investigations  of  the  United  States  Department  of  Agricul- 
ture have  been  stored  in  an  artificially  refrigerated  room  in  which 
the  temperature  could  be  varied  as  desired.  It  has  beer,  the  custom 
in  storing  potatoes  in  this  room  in  the  fall  to  reduce  the  temperature 
as  rapidly  as  possible  until  it  reached  40  degrees  after  which  it 
was  held  at  that  point  until  about  February  1,  when  the  temperature 
was  gradually  lowered  until  it  reached  about  35  degrees.  I^sually  the 
temperature  was  allowed  to  fluctuate  between  37  and  35  degrees. 
This  practice  has  served  to  hold  the  tubers  in  perfect  condition 
so  far  as  firmness  and  dormancy  are  concerned.  Eemembering  that 
the  sole  function  of  storage  is  to  preserve  the  stored  product  in 
as  nearly  its  original  condition  as  possible,  it  would  seem  that  the 
maximum  temperature  at  which  the  tubers  can  be  held  and  still 
remain  firm  and  dormant  should  be  regarded  as  the  most  desirable 
one  to  use. 


EFFECTS  OF  LOW  TEMPERATURE  209 

Butler's  studies-  led  liim  to  coiidude  that  a  temperature  of 
3.74  degrees  C.  or  approximately  39  degrees  F.  was  sufficiently 
low  to  retard  germination  indefinitely.  He  also  found  that  germi- 
nation could  be  more  completely  arrested,  in  air  nearly  devoid  of 
oxygen  (dead  air)  at  a  temperature  of  9.31  degrees  C.  (practically 
44  F.)  than  in  free  air  at  3.74  degrees  C.  In  a  later  publication 
Butler-*  says,  *'The  temperature  of  storage  for  domestic  use 
should  be  46  degrees  F.  or  as  near  this  temperature  as  is  consistent 
with  proper  keeping.  At  lower  temperature  than  46  degrees  F. 
potatoes  become  more  or  less  sweet  and  watery,  conditions  that  are, 
culinarily,  very  undesirable.  Storage  in  dead  air  is  open  to  the 
same  objection  as  storage  at  low  temperature." 

Recent  studies,  undertaken  by  the  writer  in  the  fall  of  1918,  and 
continued  throughout  the  whole  of  1919,  have  demonstrated  that 
tlie  germination  of  potatoes  can  be  arrested  when  stored  at  a  tem- 
perature of  40  degrees  F. 

Conclusion. — A  temperature  of  about  36  degrees  is  sufficiently 
low  for  all  practical  purposes,  and  in  the  earlier  stages  of  the 
storage  period  a  temperature  of  40  to  43  degrees  is  probably  just 
as  efficient  as  a  lower  one. 

When  potatoes  are  first  stored  every  effort  should  be  made  to 
reduce  the  temperature  as  quickly  as  possible.  This  is  particularly 
desirable  if  the  Aveather  is  warm  when  they  are  dug,  as  they  absorb 
heat  readily  and  also  develop  heat  rapidly  when  stored  in  bulk 
under  the  conditions  mentioned.  In  natural  storage  this  is  most 
easily  accomplished  by  a  little  attention  to  the  opening  of  doors 
and  ventilators  in  the  evening,  when  the  nights  are  cool,  and  closing 
them  early  in  the  morning. 

Chemical  Effects  of  Low  Temperature  on  the  Tuber. — It  has 
long  been  recognized  that  when  potatoes  are  subjected  to  temperature 
in  the  vicinity  of  the  freezing  point  of  water,  32  degrees  F.  for  any 
considerable  period  there  is  an  appreciable  accumulation  of  sugar 
in  the  tuber  which,  when  cooked,  imparts  or  a  more  or  less  sweetish 
taste  to  the  flesh.  This  condition  of  the  tuber  may  or  may  not 
be  objectionable,  according  to  whether  it  is  or  is  not  intended  for 
immediate  table  use  or  removal  from  storage.  In  some  recent 
studies  by  Appleman  (I.e.  p.  330)  it  was  found  that  the  exposure 
of  these  tubers  for  a  week  to  a  temperature  of  from  70  to  75 
degrees  was  sufficient  to  transform  four-fifths  of  the  sugar  accumu- 
lation into  starch.  These  results  would  indicate  that  a  sugar 
accumulation  in  potato  tubers  is  not  such  a  serious  matter,  unless 


210  POTATO  STORAGE  AND  SHRINKAGE 

they  are  desired  for  immediate  use.  The  phenomenon  of  sugar 
accumulation  in  the  potato  is  an  interesting  one,  because  it  is  a 
direct  result  of  throwing  the  life  processes,  continually  going  on 
within  the  tuber,  out  of  equilibrium  through  a  lowering  of  the 
temperature.  Appleman  says  {I.e.  p.  330),  "At  46  to  50  degrees 
F.,  the  process  of  respiration  and  synthesis  (in  the  potato)  of 
starch  from  sugar  consumes  all  the  sugar  that  is  formed  by  the 
action  of  the  diastase ;  therefore  no  sugar  accumulates.  Below  this 
temperature,  the  two  former  processes  are  inhibited  to  a  much 
greater  extent  than  the  latter;  consequently  sugar  begins  to  accu- 
mulate. At  32  degrees  F.  respiration  and  starch  synthesis  are  so 
slight  that  a  large  percentage  of  the  sugar  formed  accumulates; 
the  sup})ly  is  greater  than  the  consumption." 

Humidity. — Very  little  information  regarding  the  proper  de- 
gree of  humidity  to  maintain  in  the  storage  house  or  room  is 
available.  The  question  as  to  whether  the  humidity  content  of 
the  air  should  be  high  or  low  is  one  to  which  the  data  at  hand 
do  not  permit  a  satisfactory  answer.  In  all  of  the  storage  work 
with  which  the  writer  has  been  associated,  an  attempt  has  been 
made  to  maintain  sufficient  moisture  in  the  air  to  keep  the  tubers 
jfirm,  and  at  the  same  time  not  have  it  so  saturated  as  to  produce 
a  film  of  moisture  over  the  surface  of  the  tuber.  Cooper  {I.e.  p.  503) 
suggests  a  humidity  of  from  85  to  90  per  cent  as  about  correct 
for  a  potato  storage  room  when  the  temperature  ranges  from  33 
to  35  degrees  F.  This  suggestion  coincides  with  our  own  observa- 
tions as,  under  the  conditions  which  have  been  mentioned,  it  has 
been  found  that  the  humidity  content  of  the  air  was  approximately 
85  per  cent.  It  would,  therefore,  seem  that  until  further  light 
has  been  thrown  upon  this  subject  as  a  result  of  careful  experi- 
mental studies,  it  is  safe  to  advise  an  air  saturation  of  about  85 
per  cent.  One  can,  of  course,  conceive  of  a  condition  where  it  might 
be  unwise  to  keep  the  air  as  moist  as  this.  For  example,  where 
storage  decays  were  present  a  drier  atmosphere  would  tend  to  check 
the  shrinkage  from  disease  to  a  greater  extent  than  that  resulting 
from  increased  transpiration  due  to  a  drier  air. 

Aeration. — The  importance  of  a  good  supply  of  pure  air  in 
the  potato  storage  house  has  not,  so  far  as  Ave  know,  been  demon- 
strated by  any  carefully  conducted  experiments.  It  seems  reason- 
able, however,  to  assume  that  it  can  hardly  be  other  than  desirable 
from  the  health  standpoint  of  the  tuber.     In  order  to  insure  an 


AERATION 


211 


ample  supply  of  pure  air  in  the  storage  house  or  room,  generous 
provision  should  he  made  for  ventilation.  Ventilators  or  air  flues 
should  be  so  provided  as  to  insure  a  rapid  and  even  distribution 
of  air  throughout  the  structure.  The  European  grower  finds  it 
advantageous  to  store  seed  potatoes  in  open  crates  or  shallow  trays 
which  are  stacked  up  in  tiers,  thereby  insuring  a  free  circulation 


Fig.  109. — Seed  potatoes  stored  in  shallow  trays  or  flats. 

of  air  around  the  tubers  (Fig.  109).  Specially  constructed  bins 
may  partially  serve  the  same  purpose.  (See  Chapter  XIV  on 
storage  house  construction.) 

In  potato  storage  house  construction  every  effort  should  be  made 
to  exclude  the  light.  Potatoes  intended  for  table  purposes  should 
not  be  exposed  to  light  any  more  than  is  absolutely  necessary  in 
the  harvesting  and  storing  of  them.  The  quality  of  the  potato 
is  very  quickly  injured  by  light.  An  exposure  of  two  or  three  days 
to  strong  light  (not  sunlight),  very  materially  affects  the  eating 
quality  of  the  potato,  and  a  long  exposure  to  even  a  very  weak  light 
is  also  injurious.  The  storage  house  or  room  should  be  kept  as  dark 
as  possible,  if  the  quality  of  the  potato  is  to  remain  unimpaired. 
14 


212         POTATO  STORAGE  AND  SHHINKAGE 

Potatoes  intended  for  seed  purposes  arc  not  injured  by  light,  in  fact 
many  of  the  best  European  growers  purposely  expose  their  seed 
stock  to  the  light  under  the  firm  conviction  that  it  starts  them 
into  growth  quicker  and  makes  more  vigorous  plants. 

On  the  subject  of  aeration  Butler-^  says,  "Aeration  should' 
be  sparingly  given  and  the  air  should  flow  in  at  the  bottom  of 
the  bins,  not  from  the  top.  Cold  air  holds  less  water  than  warm 
air,  and  cooling  the  top  of  a  bin  results  in  a  deposition  of  moisture, 
or  the  maintenance  of  too  high  an  atmospheric  humidity."  This 
statement  is  somewhat  at  variance  with  accepted  notions  concern- 
ing aeration,  though  more  or  less  in  keeping  with  present  practices, 
so  far  as  moderation  in  the  amount  of  air  admitted  into  most 
commercial  or  farm  storage  houses.  The  admission  of  fresh  air 
through  the  floor  of  the  cellar  is  i]i  line  with  what  is  already  em- 
bodied in  the  United  States  Department's  storage  house  on  Aroos- 
took Farm,  Presque  Isle,  Maine.  Fresh  air  is  brought  into  this 
house  through  an  18-inch  concrete  conduit  which  discharges  its 
flow  of  air  through  an  opening  in  the  center  of  the  driveway. 
The  Avarm  air  is  removed  from  this  house  by  means  of  two  large 
ventilators  connecting  with  roof  cupolas  (Fig.  133). 

Soundness  of  Tubers  Stored. — One  of  the  most  prolific  sources 
of  loss  in  storage  is  that  resulting  from  the  storing  of  unsound 
tubers.  Unsound  tubers  may  be  classified  under  two  heads:  (a) 
Those  that  are  mechanically  injured  such  as  bruised  or  cut  tubers ; 
(b)  those  that  are  infected  with  disease,  such  as  the  late  blight 
rot  and  the  powdery  dry  rot.  The  losses  resulting  from  mechan- 
ically injured  tubers  are  very  largely  dependent  upon  storage  house 
conditions ;  for  example,  if  the  temperature  and  humidity  are  high, 
the  shrinkage  will  be  much  greater  than  if  the  temperature  and 
humidity  are  approximately  right.  Much  also  depends  upon  the 
sanitary  condition  of  the  storage  room.  If  the  storage  house  has  been 
carefully  disinfected  before  placing  the  potatoes  in  it,  the  chances  for 
infection  of  the  cut  or  bruised  surfaces  are  largely  eliminated.  If, 
however,  unsanitary  conditions  prevail,  the  presence  of  cut  and 
bruised  surfaces  ofi'er  an  easy  point  of  infection  for  a  number  of 
storage  decay  organisms.  The  more  carefully,  therefore,  that  po- 
tatoes are  harvested  and  stored,  the  better  will  be  their  keeping 
qualities  and  the  less  the  shrinkage. 

Every  effort  should  be  made  to  remove  all  diseased  tubers  from 
those  intended  for  storage  purposes.  Ordinarily,  the  late  blight 
rot  is  the  most  serious  storage  trouble  in  the  northeastern  part  of 


SIZE  OF  STORAGE  PILE  OR  BIN  213 

North  America,  while  the  powdery  dry  rot  is  probably  the  worst 
in  the  western  states.  In  regions  where  late  blight  is  likely  to 
be  prevalent,  it  should  be  so  controlled  by  the  thorough  spraying  of 
the  growing  plants  as  to  effectually  prevent  tuber  infection.  In 
any  case,  however,  every  effort  should  be  made  to  remove  disease- 
infected  tubers  before  placing  them  in  storage. 

Freedom  from  Soil  and  Moisture. — While  it  is  recognized 
that  it  is  not  always  possible  to  harvest  the  potato  crop  in  such 
condition  as  to  insure  freedom  from  any  unusual  amount  of  soil, 
it  is  believed  that,  insofar  as  it  is  consistent  with  the  safety  of  the 
crop,  harvesting  operations  should  be  so  timed  as  to  insure  a  mini- 
mum amount  of  soil  adhering  to  the  tubers.  It  is  not  a  good 
practice,  if  obliged  to  harvest  the  crop  when  the  soil  is  too  wet  for 
good  results,  to  gather  the  tubers  as  soon  as  dug.  Advantage 
should  be  taken  of  every  opportunity  to  leave  them  exposed  to 
the  sun  and  wind  for  an  hour  or  more,  in  order  to  allow  the  excess 
moisture  to  dry  off  and  to  get  rid  of  as  much  excess  dirt  as  pos- 
sible. When  potatoes  are  stored  with  large  quantities  of  moist 
soil  adhering  to  the  tubers,  they  are  almost  certain  to  develop  a 
considerable  amount  of  heat,  especially  if  stored  in  bulk.  Piles 
of  potatoes  stored  in  this  condition  may  cause  as  large  a  volume  of 
steam  to  escape  as  might  ordinarily  be  expected  from  a  pile  of 
fermenting  manure.  It  requires  very  little  imagination  on  the 
part  of  any  thinking  person  to  figure  out  that  potatoes  stored  under 
such  conditions  are  much  more  likely  to  decay;  and  even  if  no 
decay  does  occur,  to  realize  that  when  the  tubers  are  subjected  to 
such  high  temperatures,  the  transpiration  losses  are  very  greatly  in- 
creased. Let  us  not  forget,  therefore,  that  dirt  and  moisture  are 
undesirable  factors  in  potato  storage,  and  make  every  effort  to  store 
clean  and  dry  tubers. 

Size  of  Storage  Pile  or  Bin. — It  is  a  bad  practice  to  store 
potatoes  in  large  piles  or  bins  without  some  provision  being  made 
to  ventilate  the  pile.  In  many  instances,  potatoes  are  piled  to  a 
depth  of  from  10  to  15  feet  and  correspondingly  large  in  the  other 
two  dimensions.  If  the  tubers  are  reasonably  dry,  free  from  dirt 
and  well  ripened,  no  serious  harm  may  result  from  storing  in 
such  large  piles.  Under  such  conditions,  whatever  injury  they  may 
sustain  will  be  incurred  in  putting  them  in  the  storage  house  or 
bin,  and  the  crushing  or  cracking  of  those  at  the  bottom  of  the 
pile  by  the  excessive  weight  of  those  above.  On  the  other  hand, 
if  the  crop  is  harvested  when  the  ground  is  wet,  and  goes  into  storage 


214  POTATO  STORAGE  AND  SHRINKAGE 

under  the  conditions  mentioned  in  the  preceding  paragraph,  it  is 
dangerous  to  store  to  a  greater  depth  than  six  feet;  if  the  bin 
or  storage  space  is  a  large  one,  ventilator  shafts  should  be  inserted 
in  it  at  intervals  of  six  to  eight  feet  apart.  These  shafts  are  easily 
constructed  and  may  be  of  any  diameter  desired.  They  may  be  either 
square  or  rectangular  in  shape.  If  square,  a  dimension  of  18  by 
18  inches,  or  2-4  by  24  inches  will  be  found  convenient.  A  simple 
form  of  construction  consists  in  the  use  of  2  by  4  uprights  as  corner 
supports,  upon  which  are  nailed  four  or  five-inch  strips  of  inch 
lumber,  so  spaced  as  to  give  one  to  one  and  a  half  inch  openings  be- 
tween each  strip.  These  air  shafts  may  be  made  any  height  desired, 
and  should  be  placed  in  position  as  the  bin  is  filled.  Another  method 
is  to  use  ventilated  division  walls,  so  constructed  as  to  leave  an 
air  space  in  the  centre  of  the  wall,  see  figure  109  in  chapter  on 
storage  house  construction. 

Storage  Shrinkage. — The  shrinkage  involved  in  the  storage  of 
potatoes  from  Autumn  until  late  Spring  may  vary  from  less  than 
4  to  over  20  per  cent  by  weight,  depending  upon  the  type  of  storage 
house  used,  the  care  given  to  maintaining  the  proper  temperature 
and  humidity,  and  the  condition  of  the  tubers  when  placed  in 
storage.  The  natural  and  inevitable  losses  in  storage  are  those  in- 
volved in  the  transpiration  and  respiration  processes  continually 
going  on  in  all  living  matter. 

Shrinkage  Due  to  Transpiration  and  Respiration. — Com- 
paratively little  attention  has  been  paid  to  the  moisture  shrinkage 
of  potatoes  in  storage,  by  the  potato  growers  of  the  United  States, 
and,  with  but  one  or  two  exceptions,  such  data  as  have  been  pub- 
lished are  not  of  scientific  value,  as  they  do  not  represent  carefully 
observed  temperature  and  humidity  conditions  in  the  storage  room. 

An  examination  of  the  literature  on  the  subject  disclosed  the 
fact  that  French  and  German  investigators  have  made  a  more  or 
less  careful  study  of  the  question  and,  in  some  respects,  have  secured 
very  interesting  data.  For  the  most  part,  however,  their  observa- 
tions were  made  on  tubers  stored  at  a  much  higher  temperature  than 
growers  in  this  country  would  consider  suitable  for  the  potato.  The 
temperatures  at  which  most  of  their  experimental  work  was  con- 
ducted varied  from  43  to  52  degrees  F.,  and,  in  some  instances 
(Nobbe's),  much  higher  than  this. 

Foreign  and  American  Investigations. — In  1865,  Xobbe^  re- 
ported the  results  of  his  experimental  studies  concerning  the  loss 
of  water  and  carbonic  acid  gas  from  potato  tubers  in  storage.     His 


FOREIGN  AND  AMERICAN  INVESTIGATIONS  215 

studies  covered  the  period  between  December  13  and  June  7. 
Unfortunately,  Nobbe's  observations  were  based  on  but  two  selected 
tubers  in  each  lot  studied,  a  quantity  much  too  small  for  experi- 
mental purposes.  It  is  thought  desirable,  however,  to  present  it, 
in  order  to  show  the  character  of  the  data  taken.  Nobb'e  so  ar- 
ranged his  experiment  that  it  involved  eight  separate  conditions, 
or  factors.  Each  of  the  eight  lots  of  tubers  was  subjected  to  the 
following  factors: 

Decrease  in  Weight 

1.  Cool-dry-light   (50  to  61  F.)    34.05  grms. 

2.  Warm-dry-light   (77  to  05  F.)    57.25  grma. 

3.  Cool-moist-light    20.15  grms. 

4.  Warm-moist-light     57.65  grms. 

5.  Cool-dry-dark    34.45  grms. 

6.  Warm-dry-dark     63.25  grms. 

7.  Cool-moist-dark     13.35  grms. 

8.  Warm-moist-dark  62.10  grms. 

Inasmuch  as  Nobbe  fails  to  state  the  original  weight  of  each  lot 
of  tubers,  the  data  given  lose  much  of  their  significance,  as  it 
is  impossible  to  compute  the  actual  percentage  loss.  The  signif- 
icant factor  determining  loss  is  temperature.  Light  influence  in 
this  experiment  appears  to  be  a  negligible  one.  In  the  case  of 
dry  versus  moist-.storage  air  conditions,  an  appreciable  decrease 
in  Aveight  is  noted  for  those  stored  in  dry  chambers.  An  interest- 
ing feature  in  Nobbe's  paper  is  that  pertaining  to  his  determination 
of  the  relative  proportion  of  moisture  and  carbonic  acid  gas  loss 
in  storage.  According  to  his  figures,  the  ratio  of  gas  to  water 
is  1  to  3.5. 

Mertzel  and  Lengerke's  Agricultural  Calendar  for  1891,  p.  151, 
contains  data  regarding  the  decrease  in  weight  of  100  kilos  of 
potato  tubers  in  storage,  but  does  not  vouchsafe  any  information 
regarding  the  source  of  the  data.  The  observations,  as  reported, 
extend  from  the  end  of  October  to  the  end  of  May.  The  per- 
centages of  loss  in  weight  are  presented  by  months. 

November    56  per  cent. 

December     2.58  per  cent. 

January    1.00  per  cent. 

February    1.40  per  cent. 

March    1.06  per  cent. 

April    1.40  per  cent. 

May     2.00  per  cent. 

Total   loss    10.00  per  cent. 


216  POTATO  STORAGE  AND  SHRINKAGE 

In  1891,  Wollny,^"'  after  reviewing  Nobbe's  investigations  at 
some  length,  presents  the  results  of  his  own  studies  on  the  moisture 
loss  sustained  in  storage  of  a  dozen  varieties  of  potatoes.  His 
observations  were  made  on  100  earefull}^  selected  tubers  of  each 
variety  during  the  period  from  Octol)er  5  to  May  1.  Each  lot  was 
weighed  at  the  beginning  of  the  experiment,  after  which  the  pota- 
toes were  placed  in  tin  containers  and  stored  in  a  dry,  deep  cellar, 
in  Avhich  the  proper  light,  and  a  rather  constant  temperature 
(from  43  to  52  degrees  F.),  were  maintained.  The  subsequent 
weighings  were  made  on  the  first  and  fifteenth  of  each  month. 

The  total  loss  in  weight  for  each  variety  during  tlie  whole 
period  was  as  follows : 

Blue  Princess 4.55  per  coiit. 

Six    Weeks     4.87  jjer  cent. 

Late   Rose    5.27  per  cent. 

Gold  Else   5.48  per  cent. 

Sovereign    5.71-  per  cent. 

Early    Rose    6.07  per  cent. 

Marmont     6. 40  per  cent. 

Achilles (5.49  per  cent. 

Snowflake    0.65  per  cent. 

Lubenauer    6.78  per  cent. 

White    Rose     7.28  per  cent. 

King  of  the  Earlies   8.48  per  cent. 

Average   loss    6.17  per  cent. 

Wollny's  conclusions  were  that  the  reduction  in  weight  of 
potatoes  in  storage  iu  a  cool,  dry,  and  moderately  light  place, 
is  greatest  immediately  after  harvest,  diminishing  continually  from 
that  time  until  March,  but  increasing  from  then  on. 

He  concluded  also  that  the  apparent  differences  in  percentage 
loss  between  the  different  varieties  of  potatoes  during  storage  do 
not  stand  in  any  conformable  relation  to  the  size  of  the  tuber,  nor 
to  the  length  of  the  vegetative  period  of  the  variety. 

Denaiffe/'  in  1907,  reports  a  somewhat  similar  investigation 
to  Wollny's.  His  studies  included  eight  varieties,  on  which  he 
observed  the  decrease  in  weight  of  tubers  for  a  })eriod  of  about 
14  months.  The  quantity  of  each  variety  used  was  100  kilograms, 
on  which  readings  were  taken  each  montli. 

In  discussing  his  data,  Denaiffe  states  that  the  loss  in  weight 
during  storage  varies  with  tlie  varieties,  and  is  not  tlie  same  for 
all  months. 


TAFT  AND  HEDRICK  217 

The  losses  sustained  by  each  variety  from  December  1,  1904, 
to  June  1,  1905,  were  as  follows: 

Up-to-date    5.0     per  cent. 

Imperator     5.15  per  cent. 

Professor  ]\l;ierfker    6.55  per  cent. 

Quarantaiiie   de   la   Ilalle    6.60  per  cent. 

Parisienne    7.10  per  cent. 

Belle  de  Fontonay    ^ 7.30  per  cent. 

Saucissc   rouqe    .  .    9.35  per  cent. 

Royal  kidney  9.50  per  cent. 

Average  loss    7.00  per  cent. 

This  observation  is  condrniatory  of  tliat  of  Wolhiy,  and  simply 
emphasizes  the  fact  that  all  varieties  do  not  give  similar  responses 
in  storage.  The  maturity  of  the  variety,  the  character  of  the 
skin,  and  its  period  of  winter  rest  are  factors  which  influence  the 
activity  of  the  transpiration  and  respiratory  processes  of  the  tuber. 
A  comparison  of  these  losses  by  months,  as  noted  by  Wollny  and 
Denaiffe,  indicates  somewhat  wide  variations  in  the  percentages  of 
loss  in  weight  under  (lifFeroiit  environmental  conditions  and  with 
different  varieties. 

Comparison  of  Wollny's  and  Denaiffe's  data,  giving  per- 
centage of  loss  by  months: 

Date  Wollny,  (12  var.)  Denaiffe  (.S  var.) 

Oct.  5  to  Nov.  1 2.02  per  cent 

Xovenilier     1.18  per  cent ■ 

December     0.75  per  cent 1.125  per  cent. 

January     0.50  per  cent 1.193  per  cent, 

February    0.81  per  cent 0.725  per  cent. 

March     0.41  per  cent 1.218  per  cent. 

April     0.50  per  cent 1.0       per  cent. 

May    1.743  per  cent. 

Given  similar  conditions  and  varieties,  well-ripened  tubers 
shoidd  not  show  any  appreciable  loss  in  weight  during  the  first 
few  mouths  of  storage,  jirovided  a  uniform  and  moderately  low 
temperature  is  maintained. 

For  present  uses,  Wollny's  data  are  more  valuable,  in  that  they 
account  for  the  loss  in  weight  from  October  5,  as  against  Decem- 
her  1  in  Denaiffe's  studies. 

Taft  and  Hedrick  "  report  a  loss  in  weight  on  a  barrel  of  pota- 
toes, stored  in  a  basement  cellar  from   September   30  to   March 


218 


POTATO  STORAGE  AND  SHRINKAGE 


28,  of  5  per  cent,  and  G.5  per  cent  from  March  28  to  May  1 — 
or  a  total  loss  of  11.5  per  cent.  It  is  self-evident  that  the  heavy 
loss  incurred  during  the  latter  period  must  have  been  the  result 
of  high  temperature  and  possibly  of  germination.  Fraser,"  (p.  151), 
reports  a  loss  of  12  per  cent  in  Sir  Walter  Raleigh  stored  in  crates 
in  a  cool  cellar  from  November  6,  1903,  to  April  27,  1904,  Avhile 
under  similar  conditions.  Carman  No.  3  showed  a  decrease  in 
weight  of  nearly  10  per  cent. 

Butler's  studies,-''  (p.  4),  on  the  relation  of  temperature  to  loss 
in  weight  of  Green  Mountain  potatoes  placed  in  storage  November 
12,  shows  the  following  percentage  losses  for  30,  60,  90,  120,  150, 
180  and  210  day  periods  at  three  temperatures. 


of  Temperature  on  Respiration  and  Transpiration  Losses  from  Potatoes. 


Per  cent  of  loss  in  weight  after 

Mean  temperature 
of  storage 

30  days 

60  days 

90  days 

120  days 

150  days 

ISO  days 

210  days 

39  degrees  F. 
48  degrees  F. 
60  degrees  F. 

0.58 
1.26 
1..52 

1.43 
2.53 

2.77 

1.43 
3.37 
4.01 

2.29 
4.21 
G.65 

2.58 

7.18 
11.56 

2.15 

2.44 

A  comparison  was  also  made  of  the  respiration  and  transpi- 
ration losses  from  two  lots  of  Greeu  Mountain  potatoes  removed 
from  ordinary  storage  on  January  26  and  subjected  to  a  tempera- 
ture of  50  degrees  F.,  one  lot  being  exposed  to  a  free  circulation 
of  air,  while  the  other  was  stored  in  dead  air.  The  percentage 
loss  at  the  end  of  90  days  was  8.96  from  those  in  free  air  and 
1.35  from  those  in  dead  air.  At  the  end  of  119  days,  these  per- 
centages had  increased  to  17.24  and  2.79  respectively.  Those 
exposed  to  free  air  began  to  germinate  in  43  days,  while  those  in 
dead  air  remained  dormant. 

Numerous  inquiries  by  the  writer  regarding  potato  storage 
losses  have  invariably  elicited  from  the  grower  or  shipper  the  reply 
that  no  definite  effort  has  been  made  to  determine  the  losses,  either 
collectively  or  separately.  It  is  the  general  impression  that  the 
losses  from  moisture  and  decay  vary  from  10  to  20  per  cent.  Under 
exceptionally  good  storage  conditions,  transpiration  and  respiration 
losses  of  less  than  4  per  cent  have  been  reported.  Such  losses  do 
not,  of  course,  take  into  consideration  those  involved  in  the  ger- 
mination of  the  tubers.     In  the  process  of  germination  both  the 


QUESTIONS  ON  THE  TEXT  219 

respiration  and  transpiration  processes  are  quickened,  because  the 
temperature  of  the  room  must  be  relatively  high  to  permit  of  germi- 
nation; and,  in  addition  to  this,  the  starch  content  of  the  tuber  is 
very  rapidly  transformed  into  sugar.  Under  these  conditions,  the 
shrinkage  is  heavy  and  the  quality  of  the  flesh  rapidly  deteriorates. 

QUESTIONS    ON    THE   TEXT 

1.  What  is  the  primary  object  of  storage?     Secondary  object? 

2.  What  are  the  chief '  sources  of  loss  during  the  storage  period? 

.3.  In   what   sections   of   the   country   is    potato    storage   of    the   greatest 
importance?     Give  reasons. 

4.  Upon  what   factors   is   successful   storage  dependent? 

5.  Upon  what  are  based  the  data  regarding  the  proper  storage  tf^mperature 

for  potatoes? 

6.  What  does  Dr.  Parisot  regard  as  the  ideal  temperature? 

7.  What   is   the    freezing   temperature   of    the   potato    as    determined    by 

Dr.  Appleman? 

8.  What  temperatures  were  found  satisfactory  by  the  Office  of  Horticul- 

tural   and    Pomological    Investigations    during    the    past    several 
years  ? 

9.  On  first  storing  potatoes,  what  attention  should  be  given  to  the  manipu- 

lation of  the  storage  house? 

10.  What  is  the  chemical  effect  of  prolonged  low  temperatiire  on  the  po- 

tato tuber?     How  serious  is  this? 

11.  How  may  such  an  effect  be  dissipated? 

12.  What  information  have  we  on  the  subject  of  humidity  in  the  storage 

house  ? 

13.  Of  what  importance  is  the  question  of  aeration  on  potato  storage? 

14.  What  are  Butler's  suggestions  regarding  aeration?     How  much  are  his 

ideas  at  variance  with  current  notions? 

15.  Why  should  there  be  an  effort  made  to  exclude  light  from  the  storage 

house  ? 

16.  What  is  one  of  the  most  prolific  sources  of  loss  in  the  storage  house? 

17.  Under  what  two  heads  may  unsound  tubers  be  classed? 

18.  What    precautions    shoxild    be    observed    relative    to    the    exclusion    of 

diseased  or  injured  tubers? 

19.  Why  have  the  tvibers  free  from  an  excess  of  soil  or  of  moisture  before 

storing  them  ?     How  ? 

20.  What  fjactors  limit  the  size  of  the  storage  pile  or  bin? 

21.  What  should   be  the   limiting   factors  governing  the  size   of   the   pile 

or  bin? 

22.  What  percentage  of  shrinkage  is  usually  entailed  in  storage? 

23.  What  information  have  we  upon  the  actual  natural  losses  in  storage? 

24.  What  results  did  Nobbe  secure  from  his  storage  studies? 

25.  What  losses  are  shown  in  the  data  published  in  Mertzel's  and  Lengerke's 

Agricultural  Calendar  for  1891? 

26.  In   Wollny's   investigation   of   the  moisture  loss   sustained   in   storage, 

what  evidence  is  seen  that  he  took  proper  precautions  to  secure 
desirable  material  for  study? 

27.  What  is  there  to  show  that  the  temperature  at  which  the  tubers  were 

stored  was  sufficiently  low  to  determine  the  minimum  loss  from 
transpiration  and  respiration? 


220  POTATO  STORAGE  AND  SHRINKAGE 

2S.  Can  you  explain  why  the  results  secured  show  such  variations  in  the 

percentajie  of  loss  of  the  12  varieties  studied? 
2!(.  What  were  Wollny's  conclusions  regardinj^  the  losses? 

30.  What  was  the  nature  of  Uenaiffe's  investigations? 

31.  Compare  the  results  secured  by  DenaiiTe  with  those  of  Wollny? 

32.  From  a  scientific  as  well  as  a  practical  standpoint,  wiiich  c"f  the  two 

sets  of  data  has  the  greatest  value?     Give  reasons. 

33.  What  loss  in  weight  did  Taft  and  Hedrick  observe  in  their  experiment? 

34.  What  loss  did  Fraser  note  in  his  studies? 

35.  What  losses  did  Bixtler  note  in  his  investigations? 

36.  What  is  the  general  impression  by  growers  and  doalers  regarding  the 

percentage  of  storage  loss? 

37.  Under  good   storage  conditions  and  with   sound   stock,   how   low  may 

the  percentage  of  loss  be? 

QUESTIONS   SUGGESTED  BY  THE  TEXT 

1.  Do   local  growers   or  dealers   store  potatoes? 

2.  Ascertain  the  various  lengths  of  storage  periods. 

3.  What  examples  can  you  find  of  serious  rotting  and  heating? 

4.  Obtain  examples  in   homes  or  boarding  places  of   potatoes   that  have 

become  sweet  or  watery  from  storage. 

5.  Trace  such  example  and  determine,  if  possible,  how  and  where  sloi-od, 

and   temperature  of   same. 

References    Cited 

1.  Applemax,   C.   O.      1912.      Changes   in   Irish  potatoes   during   storage. 

Md.  Sta.  Bui.  167:   330,  May,  1912. 

2.  BiTTLER,  O.     1910.     The  effect  of  the  environment  on  the  loss  of  weight 

and  germination  of  seed  potatoes  during  storage.     Jour.  Am.  »S'oc. 
Agron.  11:   114-118,  March,  1919. 
2a. 1919.     Storage  of  potatoes.     N.  n.  f^ta.  Circ.  20:    7,  June,   1919. 

3.  CooPEK,  M.     1914.     Practical  Cold  Storage,  2nd.  ed.     1914:  503. 

4.  CoREETT,  L.  C.     1913.    Garden  Farming.     1913:369. 

5.  Dexaiffe,   H.      1907.      Experiences    sur   la   conservation   des   pommes 

de  terre  et  leur  perte  de  poids.  (Experiments  in  the  conservation 
of  potatoes  and  their  loss  in  weight).  Le  Jardin  21:  76-79, 
illus.     1907. 

6.  Frasek,  S.     1905.     The  Potato.     1905:  150. 

7.  Grubb,  E.  H.,  and  W.  S.  Guilford.     1912.     The  Potato.     1912-132. 

8.  NoBBE,  F.     1865.     Ueber  die  zu  und  abnahmen  des  starkegehalts  der 

kartoffelknolle.     Landioirthsch,   Versuchsta.   7:    451-463,    1865. 

9.  Taft,  L.  R.,  and  U.  P.  Hedrick.      1895.     Potatoes.     3Iich.   Sta.  Bui. 

119:    1-16,  Feb.,  1895. 

10.  Wollny,    E.      1891.      Untersuchungen    iiber    den    gewichtsverlust    und 

einige  morphologische  veriinderungen  der  kartoffelknollen  bei  der 
auflochwahrung  im  keller.  Agr.  Physik.  14:  286-302,  1899  (see 
p.  291). 

11.  Wright,  W.  P.,  and  E.  J.  Castle.     1906.     Pictorial  Practical  Potato 

Growing.     1906:  97. 


CHAPTER  XTV 

TYPES  OF  STORAGE  HOUSES,  THEIR 
CONSTRUCTION  AND  COST 

In  the  present  discussion  of  types  of  storage,  either  in  especially 
constructed  storage  houses  or  otherwise,  it  is  our  purpose  to  briefly 
trace  its  development  from  the  primitive  to  the  modern  up-to-date 
artificially  refrigerated  structure.  Storage  in  its  primitive  state 
consisted  in  burying  the  product  in  the  soil,  or  storing  it  in  a  cave 
or  excavated  chamber  of  some  sort.  As  agriculture  developed, 
and  became  more  specialized,  and  wealth  increased,  better  and 
more  expensive  types  of  storage  w^ere  demanded,  in  order  to  meet 
tlie  growing  necessities  of  large  urban  populations.  In  the  case  of 
the  potato,  one  of  the  simplest  and  most  primitive  forms  of  storage, 
commonly  known  as  pitting,  is  still  practised  to  a  limited  extent 
in  some  sections  of  the  country. 

The  types  of  storage  to  which  consideration  is  given  in  the 
ensuing  portion  of  this  chapter  embrace  everything  that  may 
justly  be  regarded  as  applicable  to  the  potato.  The  house  cellar  is 
omitted,  because  it  is  assumed  that  it  does  not  require  discussion  or 
explanation,  other  than  to  say  that  in  special  late  potato-producing 
sections  it  is  not  generally  employed  for  storage  purposes.  The 
following  types  are  believed  to  represent  those  that  are  now  gener- 
ally employed  for  potato-storage  purposes : 

1.  Pitting. 

2.  The  dugout,  or  cellar  type  of  storage  house. 

3.  The  insiilated  wooden  structure. 

4.  The  Aroostook,  Maine,  type. 

.').  The  artificially  refrigerated  structure. 

Pitting. — Potatoes  may  be  successfully  stored  in  pits  if  good 
drainage  is  provided  and  sufficient  covering  applied  to  thoroughly 
insulate  the  stored  tubers  from  external  heat  and  cold.  Strictly 
speaking,  the  term  pitting  is  somewhat  misleading;  it  does  not 
necessarily  imply  an  actual  pit  in  the  ground,  as  will  be  noted  in 
the  discussion  that  follows. 

In  pitting  potatoes,  good  drainage  is  the  first  consideration  in 
selecting  the  site.    The  land  must  either  be  well  drained  naturally. 

221 


222 


TYPES  OF  STORAGE  HOUSES 


or  else  so  situated  as  to  make  good  drainage  possible.  Little,  if 
any,  excavation  is  ordinarily  made  in  pitting  potatoes,  aside  from 
making  a  smooth  surface  on  which  to  pile  the  tubers. 


Fig.  110. — First  steps  in  pitting  potatoes. 

Shape  of  Pile. — The  shape  of  the  pit  should  l)e  that  of  a  paral- 
lelogram, rather  than  square  or  circular.  The  customary  practice 
is  to  pile  the  tubers  in  a  ridge  or  inverted    A -shaped  fashion  as 


Fig  111. — Exterior  view  of  a  large  potato  storage  cellar  in  process  of  construction  on 
the  Sweet  ranch,  Carbondale,  Colorado,  showing  construction  of  vestibule  entrance  and  the 
covering  of  roof  with  straw. 

shown  in  (Fig.  110).    When  piled  in  this  way,  it  exposes  a  greater 

area  of  the  pile  to  the  air  and,  when  covered,  sheds  rain  much  better. 

Its  size  is,  of  course,  determined  by  the  quantity  of  potatoes 

to  be  stored,  and  the  limit  of  safety  as  regards  danger  from  loss  if 


PROVISION  FOR  VENTILATION 


223 


stored  in  too  large  a  pile;  because,  as  the  size  of  the  pile  increases, 
the  difficulty  of  cooling  it  quickly  is  enhanced ;  and,  should  decay  in 
the  tubers  become  active,  greater  losses  are  sustained  in  large  than 
in  small  i)iles.  Generally  speaking,  the  limit  of  size  should  be 
from  300  to  350  bushels  or  half  a  carload. 


porting  : 


■w  of  same  cellar  showing  roof  construction  and  method  of  sup- 
ly  through  the  storage  cellar.     Messrs.  Lou  D.  Sweet  on  the 


leit  and  F.  E.  Sweet  on  the  right. 

Provision  for  Ventilation. — When  pitting  the  tubers,  some 
provision  should  be  made  for  ventilation.  A  common  practice 
abroad  is  to  take  a  handful  of  rye  or  wheat  straw  and  stand  it  in 
a  vertical  position  on  top  of  the  pile  while  the  straw  and  earth 
covering  is  being  applied,  after  which  it  is  pulled  out,  thus  providing 
a  vent  for  the  escape  of  heat  and  moisture.  Probably  a  better 
practice  is  to  construct  a  small  ventilator  shaft  of  six  or  eight 
inches  diameter  out  of  inch  lumber.  Bore  numerous  holes  an  inch 
or  so  in  diameter  in  the  lower  portion  of  the  shaft,  and  insert  it 


224 


TYPES  OF  STORAGE  HOUSES 


in  the  centre  of  the  pile  as  tlie  tubers  arc  bein^^  ])itte(L  Tlie  nearer 
it  extends  to  the  bottom  of  the  pile,  the  more  perfect  the  ventilation 
provided.  It  should  extend  three  or  four  feet  above  the  tubers,  so 
that  when  the  covering  is  applied  it  will  protrude  18  to  24  inches 
above  it.  The  ventilator  should  be  provided  with  a  cap  to  prevent 
the  entrance  of  snow  or  rain.  In  severe  weather  it  should  be 
stopped  with  straw.  If  the  pile  is  more  than  ten  feet  in  length, 
a  second  ventilator  should  be  inserted.  A  good  rule  to  follow  is 
to  have  a  ventilator  every  eight  feet.  This  insures  reasonably  good 
ventilation  of  all  uortions  of  the  pile. 


-aftS» 


Fig.  113. — Completed  structure  showing  cribbed  vestibule  on  the  Sweet  ranch, 
Carbondale,  Col. 

Protection  Against  Frost. — As  soon  as  the  potatoes  are  in 
position,  they  should  be  immediately  covered  with  a  sufficient  quan^ 
tity  of  straw  or  marsh  hay  to  exclude  light.  The  pitted  tubers 
should  be  left  in  this  condition  as  long  as  they  are  safe  from  frost. 
This  gives  them  a  chance  to  go  through  the  sweating  process  and 
get  thoroughly  cooled  off,  after  which  there  is  little  danger  from 
heating  and  sweating  when  the  final  covering  is  applied. 

As  soon  as  the  nights  become  frosty,  apply  a  heavy  layer  of 
straw,  so  that  when  compacted  with  soil  it  will  be  about  six  inches 
thick.  On  top  of  the  straw  apply  a  six  inch  layer  of  soil.  Before 
the  ground  freezes  too  solid,  apply  another  heavy  layer  of  straw 
and  a  similar  one  of  soil.  Ordinarily,  two  heavy  layers  of  both  straw 
and  soil  furnish  sufficient  insulation;  but  where  extremely  cold 
weather  prevails,  a  third  layer  may  be  advisable.     When  sound 


STORAGE  HOUSES  PROPER 


225 


potatoes  are  pitted  in  this  manner,  there  is  practically  no  risk  in- 
A'olved,  as  they  are  almost  certain  to  come  out  in  good  condition 
in  the  Spring. 

The  advantage  of  pitting  potatoes  is  that  it  is  a  cheap  form 
of  storage. 


Fig.  114. — A  good  example  of  a  sod-walled  potato  storage  house  near  Greeley,  Col 
This  house  is  provided  with  ridge  and  side  ventilators. 

The  disadvantage  of  pitting  is  that  in  severe  weather  the  pota- 
toes are  not  accessible,  consequently  any  sudden  rise  in  market 
prices  cannot  l)e  taken  ndvantage  of  by  the  grower. 


Fig.  115. — One  of  ths  cheaper  types  of  partially  ; 
with  earth  retaining  walls  and  side  roof  openings  whirh  may  bciisdl  for  tillint^  the  storage 
space  or  for  ventilation.    In  the  Greeley,  Col.,  district. 

Generally  speaking,  pitting  is  not  to  be  recommended,  except 
where  no  other  storage  facilities  are  available. 

Storage  Houses  Proper. — In  deciding  what  particular  storage 
house  is  most  suitable  to  one's  needs,  the  following  factors  should 
be  considered: 


226 


TYPES  OF  STORAGE  HOUSES 


(a)  The  temperature  and  precipitation  likely  to  occur  during 
the  storage  period;  (b)  the  character  and  cost  of  the  materials 
involved;  (c)  the  nature  of  the  soil  and  drainage;  (d)  tlie  stor- 
age period. 

It  is  apparent  to  the  reader,  that,  in  the  arid  and  semi-arid 
regions  of  the  West,  a  materially  different  type  of  construction  from 
tlint  in  use  in  the  rain-belt  section  of  the  East  might  be  permissible. 


•^    ■_  ..tt'..'^ -"{l'^  '       '  ? 

\NX.  F   "X^^ 

■:^s^^^^ 

^K^T:£!^-a^iKr^^^^l^0Skf^ 

Fig.  116. — A  well-constructed  storage  house  of  the  partially  sunken  type  with  side 
and  end  walls  of  stone.  Note  heavy  pole  rafters  covered  with  woven  fence  wire  ready  to  be 
covered  with  straw  and  soil.     In  the  Greeley,  Col.,  district. 

The  Dugout  or  Cellar  Type  of  Storage  House. — In  the  cen- 
tral and  western  ])ortions  of  tlie  United  States,  tlie  dugout  or  cellar 
type  of  storage  house  is  almost  the  only  kind  employed  in  the 
storage  of  potatoes.  It  is  found  in  its  most  primitive  state  in  the 
arid  and  semi-arid  regions  of  the  West,  and  in  its  highest  state 
of  development  in  the  north  central  tier  of  states  where  the  heavier 
rainfall  makes  water-tight  roofs  a  necessity. 

Location  and  Construction. — The  storage  house  should,  when- 
ever possible,  be  located  conveniently  to  the  dwelling  house,  be- 
cause, in  very  cold  weather,  it  usually  requires  rather  close  attention 


LOCATION  AND  CONSTRUCTION 


227 


to  guard  against  the  entrance  of  frost.  Where  side-liills,  knolls, 
or  what  are  termed  in  the  West  "hog-backs,"  consisting  of  a 
narrow  and  usuall}^  short  ridge  of  land,  are  available,  it  is  advisable 
to  take  advantage  of  them,  as  by  their  use  better  drainage  and  a 
ground  level  entrance  at  either  or  both  ends  of  the  cellar  can  be 
secured  (Figs.  Ill  to  119).    Where  the  topography  of  the  land  is 


\    i       Roof  COn'3!'3tS  of 

up  covered  with  pine 


Fig.  117. — A  cheaply  construct  i         (    u 

rough  poles  restinpc  on  the  ground  dii  .  ^  .jip.  .n  1  b\   ikIkcjjoI 

needles.    Such  a  type  of  storage  house  would  not  be  buitable  where  extremely  low  tempera- 
tures prevail. 

such  that  it  does  not  furnish  these  natural  advantages,  level  land 
may  be  used,  provided  good  drainage  can  be  secured.  In  this  case, 
the  excavation  may  vary  from  practically  nothing  where  surface 
drainage  must  be  depended  upon,  to  five  or  six  feet  where  there  is 
good  natural  or  artificial  drainage.  The  average  depth  of  the  ex- 
cavation for  the  cheaper  structures  of  this  type,  when  erected  on 
level  land,  does  not  exceed  three  feet.  The  soil  removed  from  such 
an  excavation,  particularly  if  the  structure  is  wide,  provides  ample 
15 


228 


TYPES  OF  STORAGE  HOUSES 

the   side   and   end   walls 


material  for  banking  the   side   and   end   walls   as   well   as   for   a 
roof  covering. 

Where  the  soil  is  of  such  a  character  as  to  remain  intact,  and 
an  excavation  of  sufficient  depth  can  ])e  made,  it  is  allowed  to  form 
the  side,  and  in  some  cases  the  end  walls;  the  roof  being  supported 
by  plates  resting  on  the  soil  and  an  occasional  post  to  relieve  the 
roof  i)ressure.     In  such  cases,  the  outward  thrust  of  the  roof  is 


Fig.  118. — A  storage  house  in  process  of  construction  at  Aberdeen,  Ida.,  showing  side 
walls  and  roof  covered  with  woven  wire  fencing  and  ventilators  in  side  of  roof. 

cared  for  by  cross-tieing  the  rafters  with  boards.  Where  the 
earthen  bank  of  the  excavation  serves  as  walls  to  the  storage  struc- 
ture, it  is  better  to  support  the  plate  entirely  with  ])osts  recessed 
into  the  earthen  walls  at  sufficiently  close  intervals  to  afford  the 
necessary  strength,  (Fig.  121). 

Where  the  storage  cellar  is  only  partially  below  the  level  of  the 
ground,  the  walls  are  variously  constructed.  In  the  cheapest  type 
noted,  both  side  and  end  walls  above  ground  were  constructed  out 
of  a  tough  sod  of  sedges  or  cat-tails  cut  to  uniform  size  and  laid 
up  in  brick  fashion.  These  walls  were  two  feet  or  more  in  thick- 
ness.    The  sod  walls  supported  the  plates  and  roof  in  practically 


WALL  CONSTRUCTION 


229 


the  same  manner  as  in  the  case  of  the  solid  earthen-walled  struc- 
ture (Fig.  114),  Another  cheap  structure  is  that  shown  in  figure 
117.  In  this  instance  the  excavation  was  not  over  two  feet,  and  the 
roof  consisted  of  rough  poles  covered  with  a  heavy  layer  of  pine 
needles.  Such  a  storage  house  has  little  to  recommend  it,  except 
that  of  heing  a  temi)orary  makeshift  to  tide  over  a  short  storage 
period  where  the  climate  is  reasonably  mild. 

Roof  Construction. — The  roof  of  the  cheaper  types  of  houses 
is  usually  constructed  out  of  undressed  poles,  which  may  be  laid 
sufficiently  close  togpfhor  to  serve  as  a  support  for  a  brush  or  straw 


Fig.   119. — Side   view  of  the    house  sh 
straw  and  soil  and  ventilators  capped. 


n  in  Figure 


covering,  over  which  a  heavy  layer  of  soil  (6  to  10  inches)  is  placed. 
In  the  better  constructed  houses  in  the  semi-arid  regions,  heavier 
and  more  substantial  rafters  are  used,  and  they  are  spaced  about 
twelve  inches  apart.  After  the  rafters  are  in  place,  a  heavy  woven 
wire  netting  is  stretched  over  them  and  nailed  in  place,  (Figs.  116 
and  118),  and  over  this  tlie  usual  straw  and  earth  covering 
is  applied. 

Where  a  side  hill  or  a  "hog-back''  is  available,  the  cut  or 
excavation  may  be  six  to  ten  feet  in  depth,  depending  on  the  size 
of  the  structure.  Such  a  site  makes  it  ])ossible  to  provide  a  ground 
level  entrance,  at  one  end  of  the  storage  house  in  the  case  of  the 
side  hill,  and  at  both  ends  when  advantage  can  be  taken  of  a 
"hog-back"   (Fig.  113). 

Wall  Construction. — In  addition  to  the  cheaper  types  of  wall 
construction  previously  mentioned,  it  is  well  to  consider  those  of 
a  more  permanent  nature.    These  may  consist  of  rough  or  dressed 


230 


TYPES  OF  STORAGE  HOUSES 


posts  set  from  four  to  six  feet  apart,  covered  on  the  outside  with 
rough  poles,  lumher  or  heavy  woven  wire;  or  they  may  be  con- 
structed of  masonry  or  concrete.  I'he  style  of  wall  construction 
adopted  is  very  largely  a  matter  of  choice  or  necessity.  Where 
first  cost  is  not  a  serious  consideration  it  is,  without  doubt,  more 
economical  to  build  a  substantial  structure.  The  grower  should 
not,  however,  lose  sight  of  the  fact  that  the  cheaper  house,  if 
carefully  built,  will  provide  as  good  storage  as  the  more  expensive 
one  as  long  as  it  lasts.  A  partially  sunken  house  is  sliown  in 
figure  132. 

In  the  humid  regions  of  the  north  central  and  eastern  portions 
of  the  United  States,  where  heavy  rains  would  render  straw  and 


Fig.  120. — A  frontal  view  of  the  completed  potato  storage  house  (Fig.  118)  showing 
driveway  entrance  and  ventilator  caps  raised  on  left  side. 

earth-covered  storage  houses  unsatisfactory,  they  are  constructed 
with  a  water-tight  roof.  Generally,  the  roof  is  covered  with 
rough  lumber,  tar  paper  and  shingles.  Occasionally,  it  is  sheathed 
with  matched  lumber  on  the  inside.  This  treatment  provides  a 
fairly  well  insulated  roof  which  in  winter  requires  no  additional 
protection,  except  during  extremely  cold  weatlier,  when  a  light 
covering  of  straw  or  strawy  manure  is  advisable. 

The  wall  construction  of  the  water-tight  roof  storage  house 
need  not  necessarily  differ  from  that  of  tlie  semi-arid  region  type 
except  that,  on  account  of  the  heavier  rainfall,  it  must  be  built 
sufficiently  strong  to  prevent  a  cave-in.  Where  first  cost  is  subsidi- 
ary to  durability,  it  is  generally  advisable  to  use  a  better  class  of 
luml^er  than  the  rough  undressed  ])oles.     It  may  even  be  economy, 


VENTILATION  AND  LIGHTING 


231 


where  the  materials  are  available,  to  construct  the  side  and  end 
walls  of  concrete  (Fig.  123).  In  some  of  the  better  type  western 
potato  storage  houses  observed,  the  posts  were  faced  on  two  sides 
and  the  walls  as  well  as  the  roof  were  covered  with  woven  wire  and 
straw,  (Figs.  118,  119  and  120). 

The  use  of  straw  on  the  roof,  especially  when  the  rafters  are 
spaced  and  covered  with  woven  wire,  serves  not  only  as  a  protection 


Fig.  121. — View  showing  earthen  wall  with  plate  supporting  posts  recessed   into  the 
bank.    On  the  Sweet  ranch,  Carbondale,  Col. 

against  heat  and  cold,  but  is  also  a  medium  for  the  absorption  of 
moisture  given  off  by  the  tubers  in  the  process  of  transpiration  and 
respiration.     There  is  no  drip  from  such  a  roof. 

Entrance  Way. — Whether  the  entrance  to  the  storage  cellar 
is  for  team  or  man,  on  the  level  or  an  incline,  (Figs.  113  and  120), 
it  should  be  provided  with  two  sets  of  doors  with  a  vestibule  between 
(Fig.  113)  in  the  case  of  a  ground  level  entrance;  or  bulkhead 
doors  where  it  is  not  (Fig.  120). 

Ventilation  and  Lighting. — Ample  provision  should  be  made 
in  all  dugouts  or  storage  pit  cellars  for  ventilation  and  lighting, 


232 


TYPES  OF  STORAGE  HOUSES 


where  electric  lighting  is  uot  feasible.  Many  styles  of  ventilators 
may  be  found,  but  those  shown  in  ligures  114,  115,  118  and  1:^5  are 
most  favored.  A  ventilator  should  be  so  constructed  that  it  possesses 
ample  size  to  admit  an  abundance  of  air,  and  at  the  same  time 
be  provided  with  a  swivel  or  slide  damper  which  may  be  closed  in 
severe  weather.  A  shaft  with  an  interior  diameter  of  12  by  13  or 
13  by  16  inches  should  be  sufficiently  large.  Those  with  hinged 
caps  to  exclude  rain,  snow,  or  frost,  seem  to  be  preferred.  As  a 
rule,  the  ventilators  are  placed  along  the  ridge  of  the  roof,  altliough 
numerous  structures  have  been  noted  in  which  they  were  constructed 
about  midway  between  the  ridge  and  the  plate.  See  figures  118 
and  123  for  both  })ositions. 


V 


Fig.  122. — Partially  sunken  storage  house  with  concrete  side  and  end  walls.    Jerome,  Idaho. 

To  insure  uniform  ventilation,  they  should  be  sjjaced  from  ten 
to  twelve  feet  apart. 

Interior  Arrangement. — The  interior  arrangement  of  the  stor- 
age cellar  is  very  largely  governed  ])y  its  size  and  character.  Where 
no  driveway  entrance  is  provided  and  the  house  is  narrow,  say  13 
to  20  feet,  the  entire  space  is  used  for  storage  purposes.  The  dirt 
floor  may  be  left  uncovered;  or  it  may  be  floored  over  with  rough 
luml)er  or  cemented. 

In  some  of  the  better  tyj)es  of  storage  cellars  in  which  there  is 
a  central  driveway,  the  storage  bins  on  either  side  of  it  have  venti- 
lated wooden  floors  laid  on  Joists.  The  joists,  being  placed  at  right 
angles  to  the  driveway,  provide  an  open  space  between  the  floor 
and  the  earth  beneath,  and  this,  as  Avill  be  seen  later,  furnishes 
an  open  and  unrestricted  circulation  of  air  beneath  the  bin,  (Fig. 
109).     Where  posts  are  used  which  are  faced  on  two  sides,  the 


THE  INSULATED  STORAGE  HOUSE  233 

inner  face  is  boarded  up  with  three  or  four-inch  strips  of  lumber, 
leaving  an  inch  space  between  each  two  strips.  The  division  walls 
between  the  bins  are  also  ventilated,  in  the  manner  described  for 
the  ventilation  of  potatoes  when  stored  in  large  piles.  With  such 
a  type  of  bin  construction,  a  free  circulation  of  air  is  possible  on 
all  sides.  Of  course,  it  is  realized  that  the  extra  expense  involved 
in  bin  construction  of  this  sort  is  considerable;  and  it  is  probably 
not  wholly  justified,  except  for  the  storage  of  seed  stock,  or  in 
seasons  when  frequent  rains  during  the  harvesting  period  make 
it  impossible  to  dry  the  tubers  properly  before  storing  them. 
Under  such  conditions,  the  ventilated  bin  is  decidedly  superior  to 
the  ordinary  type. 


Fig.  12^. — Potato  storage  house  with  concrete  walls,  straw  and  earthen-covered  roof 
plus  a  superimposed  wooden  shingle-covered  roof.     Greeley,  Colorado. 

Where  no  provision  is  made  for  a  driveway  into  the  storage 
cellar,  either  because  it  is  too  narrow  or  for  any  other  reason, 
the  potatoes  may  be  spouted  into  the  cellar  through  the  trap-door 
openings  in  the  roof,  (Figs.  126,  127  and  128).  This  method  of 
filling  the  storage  cellar  is  a  material  saving  of  labor,  and,  where 
a  blanket  or  apron  is  used  in  lowering  the  potatoes  from  the  spout 
to  the  floor,  they  sustain  no  more  mechanical  injuries  than  when 
unloaded  directly  from  the  driveway,  or  carried  in  by  hand. 

The  Insulated  Wooden  Potato  Storage  House. — This  type  of 
house  is  not  used  very  extensively.  It  is  better  adapted  to  southern 
than  to  northern  climatic  conditions.  The  construction  feature  of 
such  a  storage  house  is  the  thorough  insulation  of  its  walls,  ceilings, 
doors  and  windows,  (Fig.  129). 


234 


TYPES  OF  STORAGE  HOUSES 


The  type  of  house  recently  described  by  Thompson-  for  the 
storage  of  sweet  potatoes  will  serve  equally  well  for  the  Irish  potato, 
but,  in  the  case  of  the  latter,  does  not  require  artificial  heat  to  ripen 
the  tubers.  Storage  houses  of  the  type  under  consideration  must, 
in  the  North  at  least,  be  provided  with  facilities  for  heating  them 
in  extremely  cold  weather.  This  may  be  done  with  an  ordinary 
heating  stove.  They  are  not  to  be  recommended  for  northern  con- 
ditions, nor  advocated  for  the  South,  except  in  localities  where  poor 
drainage  conditions  will  not  permit  of  the  dugout  or  cellar  type 
of  storage  house.  They  are  not  recommended  on  account  of  their 
greater  cost  of  construction,  and  also  from  the  fact  that  they  do 


•SiSptllQlEl  ■ 


Fig.  124.— a  typical  Hor 
basement  cellar.    Glyndon,  Mir 


Kivcr  \alley  potato  warehouse  with  : 


not  furnish  as  good  storage  as  a  ])roperly  constructed  cellar 
storage  house. 

The  Aroostook,  Maine,  Type. — In  northern  Maine,  particu- 
larly in  Aroostook  County,  a  type  of  potato  storage  house  has  been 
developed  which  may  be  said  to  be  exclusively  confined  to  Maine. 
While  in  a  sense  it  is  a  cellar  storage  house,  yet  viewed  from  another 
standpoint  it  is  more,  because  the  true  Aroostook  storage  house 
includes  a  superstructure  over  the  cellar.  It  is  always  Cvonstructed 
on  a  side  hill  or  knoll,  and  is  always  provided  with  a  ground  level 
driveway  into  the  l)asemcnt,  and  at  the  opposite  end  has  a  driveway 
into  the  superstructure  above,  (Figs.  130,  131  and  132). 

Construction. — A  considerable  proportion  of  these  storage 
houses  are  constructed  with  concrete  basements  and  always  with  a 
wooden  superstructure.     When  the  basen;ent  walls  are  not  built 


INTERIOR  ARRANGEMENT 


235 


of  concrete,  they  may  consist  either  of  a  masonry  wall  of  stone, 
a  dry  wall,  or  a  wooden  wall  constructed  with  posts  and  rough 
siding,  or  it  may  consist  entirely  of  rough  posts.  The  floors  may 
or  may  not  be  cemented.  Usually,  the  storage  space  is  covered 
with  a  tight  wooden  floor  laid  on  joists. 

The  basements  are  usually  of  good  depth,  8  to  13  or  more  feet, 
and  their  capacity  ranges  from  2,000  to  10,000  or  more  barrels. 
Generally  speaking,  their  construction  is  faulty  with  respect  to 
ventilation,  only  an  occasional  one  being  provided  with  means  for 
ventilation,  other  than  through  trapdoors  in  the  upper  floor.  The 
storage  house  with  ventilator,  shown  in  figure  130  was  the  only 
one  the  writer  had  noticed  ])rior  to  1917.  See  the  ventilators  in 
figure  133. 


Fig.  125. — A  100,000  bushel  potato  warehouse  at  Lariuiore,  N.  D. 

In  storing  the  crop  in  the  basement,  the  bins  are  partially  filled 
from  the  lower  floor,  the  balance  being  put  in  from  above,  through 
trapdoors  on  either  side  of  the  driveway  and  over  the  bins  below. 
When  the  house  is  built  with  a  central  driveway,  it  may  also  be 
filled  in  the  same  manner. 

In  addition  to  serving  a  useful  purpose  in  filling  the  bins  and 
protecting  the  potatoes  from  inclement  weather,  the  wooden  super- 
structures of  these  storage  houses  have  various  uses,  such  as  the 
housing  of  farm  implements,  barrels,  sacks,  fertilizer  and  other 
sup])lies;  or  they  may  serve  for  the  storage  of  hay  or  grain. 

Interior  Arrangement. — Broadly  speaking,  the  interior  ar- 
rangement of  the  liasement  is  dependent  on  whether  it  is  con- 
structed with  a  central  driveway,  or  whether  the  entrance  is  at  one 
corner  of  the  building.  A  basement  with  a  central  driveway  has 
bins  on  either  side,  whereas  those  with  an  entrance  at  one  corner 


236  TYPES  OF  STORAGE  HOUSES 

vary  considerably  in  their  bin  arrangement,  depending  on  whether 
one  or  more  varieties  are  l^eing  grown  and  stored;  figures  130  and 
131  give  a  very  good  general  idea  of  the  exterior  appearance  oi"  the 
Maine  type  of  storage  house. 

The  Artificially  Refrigerated  Potato  Storage  House. — This 
type  of  storage  house,  for  potatoes  at  least,  can  hardly  be  said  to 
be  in  existence.  So  far  as  we  are  aware,  the  present  use  of  arti- 
ficially refrigerated  storage  houses  is  practically  confined  to  the 
holding  of  northern  grown  seed  potatoes  in  cold  storage  for  second 
crop  planting  in  the  South,  and  to  the  temporary  holding  of  table 
stock  in  laro'o  distributing  centres. 


Fig.  12t). — A  good  example  of  the  type  of  storage  house  in  use  in  the  Red  River  Valley 
in  Minnesota  and  North  Dakota.  This  house  has  a  water-tight  roof  with  several  openings 
in  it  to  permit  of  spouting  the  potatoes  into  the  storage  bin.    Sabin,  Minn. 

Ammonia  System. — The  system  of  refrigeration  used  in  the 
cold  storage  plants  employed  for  this  purpose  is  known  as  the 
"ammonia  system."  The  temperature  at  which  potatoes  are  held 
in  this  type  of  storage  is  usually  from  32  to  34  degrees  F. 

While  there  is  probably  little  demand  for  the  artificially  refrig- 
erated potato  storage  liouse  in  the  North,  it  is  a  questionable  point 
whether  community  cold  storage  plants  could  not  be  profitably 
employed  by  the  southern  potato  truck  grower.  If  such  houses  were 
available  in  the  South,  the  present  practice  of  moving  seed  stock 
from  northern  Maine  during  the  months  of  January  and  February, 
with  its  attendant  risk  of  frost  injury  could  be  avoided,  as,  wath 
cold  storage  facilities,  the  seed  potatoes  could  be  shipped  in  the 
Autumn.  At  the  present  time,  the  potato  storage  houses  of  the 
South  do  not  compare  at  all  favorably  with  those  of  the  North, 
being  for  tlic  most  ]iart  of  the  dugout  type  and  constructed  with 


BRINE  SYSTEM  237 

little  head-room.  They  are  wholly  inadequate  for  the  holding  of 
northern  grown  seed  and,  as  a  result,  the  stock  held  in  them  from 
November  to  February  is  usually  rather  badly  germinated.  All 
of  these  troubles  could  be  avoided  through  autumn  delivery  of 
northern  seed  stock  and  its  transference  to  the  cold  storage  house. 
Such  a  change  in  time  of  delivery  would  enable  the  grower  to 
purchase  his  seed  at  a  reduction  in  jirice  over  that  of  mid-winter 
delivery  more  than  sufficient  to  offset  the  cost  of  storage. 

Brine  System. — One  of  the  more  recent  tyjoes  of  storage  houses, 
which  may  have  a  place  in  the  storage  of  potatoes  outside  of  the 
colder  jiotato-growing  regions,  is  that  known  as  "the  Cooper  system 


Fig.    127. — Spouting  potatoes  into  storage   cellar   through  chutes  in  the 
Greeley,  Col.,  district. 

of  brine  circulation."  In  this  system,  ice  and  salt  are  used  as  a 
substitute  for  ammonia  in  cooling  the  brine.  In  "Practical  Cold 
Storage,"  pp.  660-662,  Cooper  describes  the  process  as  follows :  "In 
the  Cooper  gravity  brine  system,  the  tank,  which  contains  the  ice 
and  salt,  and  the  tank  coils,  or  primary  coils  as  they  are  called, 
are  located  at  a  higher  level  than  the  secondary  coils  which  do  the 

air  cooling  in  the  rooms When  the  tank  is  filled  with  ice 

and  salt,  the  brine  standing  in  the  primary  or  tank  coil  is  cooled, 
by  contact  with  the  ice  and  salt  which  surround  the  pipes,  to  a 
lower  temperature  than  the  brine  contained  in  the  secondary  coils. 
At  the  same  time,  the  brine  from  the  secondary  coils  rises  into  the 

primary  coils,  where,  as  it  is  cooled,  it  repeats  the  circuit 

The  term  'gravity,'  as  applied  to  this  system  of  brine  circulation, 
refers  to  the  cause  of  circulation  which  is  owing  to  the  difference  in 


238 


TYPES  OF  STORAGE  HOUSES 


specific  gravity  (weight)  between  the  cokl  brine  in  the  primary 
coils  and  the  comparatively  warm  brine  in  the  secondary  coils. 
The  temperature  of  the  circulating  brine  will  range  from  zero  to 
20  degrees  F.  It  is  comparatively  easy  to  cool  a  room  to  10  or  12 
degrees  F.  with  the  Cooper  brine  system." 

This  system  of  refrigeration  was  used  1)y  the  United  States 
Department  of  Agriculture  in  the  storage  of  potatoes  from  1911 


FiQ.  128. — Method  of  filling  a  storage  house  in  the  Greeley  district  through  openings 
in  roof.    Driveway  partially  filled  by  spouting  potatoes  through  roof  openings. 

to  1918  and  it  proved  very  satisfactory.  It  was  found  possible, 
with  proper  attention,  to  maintain  the  temperature  of  the  storage 
room  at  practically  the  same  degree  for  weeks  at  a  time,  as  shown 
by  the  thermograph  record  sheet  (Fig.  134). 

Cost  of  Construction. — Owing  to  the  wide  variation  in  cost 
of  building  material,  and  the  price  of  labor  in  different  sections  of 
the  country,  cost  figures  concerning  the  construction  of  any  par- 
ticular type  of  house  must,  of  necessity,  be  more  or  less  general  in 
their  character.     Naturally,  the  type  and  the  size  of  the  house  is 


COLORADO 


239 


largely  determined  by  the  character  of  the  material  available,  the 
climatic  conditions  and  the  storage  cai)aelty  required.  In  deter- 
mining the  size  of  storage  cellar  required  to  house  a  given  quantity 
of  tubers,  the  estimate  should  be  based  on  40  pounds  of  tubers  per 
cubic  foot  of  available  storage  space.  Figured  on  this  basis,  a  bin 
10  by  10  feet  square,  filled  to  a  depth  of  six  feet,  has  a  storage 
capacity  of  400  bushels,  or  an  average  of  four  bushels  for  every 
square  foot  of  floor  space. 


Fig.  129. — A  good  example  of  an  insulated  wooden  structure  used  for  the  storage  oi 
potatoes  in  some  localities  in  Michigan. 

Colorado. — The  following  information  concerning  the  cost  of 
construction  has  been  very  kindly  furnished  by  practical  growers. 
The  first  data  presented  are  those  given  by  Messrs.  Lou  D.  and 
Frank  E.  Sweet,  of  Carbondale,  Colorado,  and  relate  to  the  potato 
storage  house  shown  in  figure  112.  The  capacity  of  this  house  is 
stated  to  be  from  13,000  to  25,000  bushels,  depending  on  the  depth 
to  which  it  is  filled,  as  well  as  storing  in  the  driveway.  Its  cost 
is  estimated  at  $1,000.  This  cost  did  not  include  the  lumber  cut 
on  the  surrounding  mountains,  for  which  there  was  no  other  cost 
than  that  of  cutting  and  hauling.  Allowing  $300  for  the  rough 
timbers  used,  it  would  bring  the  actual  cost  to  about  $1,300.  On 
this  basis,  the  initial  cost  of  providing  storage  for  one  bushel  of 


240 


TYPES  OF  STORAGE  HOUSES 


potatoes  reduces  itself  from  10  to  5.2  cents  per  bushel,  depending 
upon  the  depth  to  which  the  tubers  are  piled.  Assuming  that 
the  average  life  of  such  a  structure  is  ten  years,  the  actual  per 
bushel  cost  of  storage  is  one  cent  and  .53  cent  respectively.  Of 
course,  these  figures  do  not  take  into  account  interest  charges 
on  the  investment. 

Fitch^  states  that  the  first  cost  of  storage  in  an  average  grade 
potato  cellar  is  about  20  cents  per  hundredweight,  or  1.2  cents 
per  bushel  on  a  ten-year  basis.  He  further  intimates  that  this  cost 
can  be  reduced  to  7  instead  of  20  cents  per  hundredweight  if  little 


Fig.  130. — Exterior  front  view  of  a  Maine  type  of  storage  liouse.  This  particuiar 
house  is  an  exception  to  the  general  rule  in  that  it  is  provided  with  a  roof  ventilator. 

regard  is  given  to  the  permanence  of  the  structure  and  farm  labor 
is  utilized  in  its  construction. 

Minnesota. — Henry  Schrocder,  of  Sabin,  IMinncsota,  sul)mitted 
the  following  figures  concerning  his  storage  cellar  shown  in  figure 
126.  This  house  is  constructed  with  wooden  walls,  and  a  water- 
tight roof.  The  walls  are  four  and  a  half  feet  below  the  surface 
of  the  ground  and  extend  four  feet  above  it.  Its  dimensions  are 
20  by  100  feet  and  it  has  an  approximate  storage  capacity  of 
10,666  bushels,  if  figured  on  the  basis  of  its  full  capacity  of  eight 
feet  in  depth.  Tt  was  constructed  at  a  cost  of  $1,200,  or  an  average 
initial  cost  of  11.25  cents  per  bushel,  or  1.125  cents  on  a  ten- 
year  basis. 

Maine. — C.  C.  King,  of  Caribou,  Maine,  submitted  the  following 
estimates  on  a  Maine  type  of  storage  house,  40  by  GO  feet,  having 
a  storage  capacity  of  4,250  to  5,500  bushels,  the  cost  of  wliich  he 


MAINE 


241 


places  at  $3,500.  The  initial  cost  of  storage  in  this  case  is  64  to 
82  cents  per  bushel.  The  longer  lil'e  oi'  such  a  structure  tends  to 
reduce  the  average  cost  of  storage  over  a  period  of  years.  King 
further  states  that  the  same  house  could  be  built  Avithout  a  con- 
crete cellar,  but  resting  on  concrete  piers,  for  about  $2,500  to 
$2,700,  According  to  King,  the  most  common  size  of  storage  house 
in  Aroostook  County,  Maine,  is  tlie  35  by  60  feet  or  the  40  by 
50  feet. 


Fig.  131. — Exterior  rear  view  of  same  house  showing  driveway  entrance  located  in  side 
of  building  at  the  rear  end. 

George  E.  Howard,  of  Dover,  Maine,  says,  "I  am  satisfied  tliat 
the  ordinary  potato  storage  house,  when  built  40  by  60  feet  with 
]tosts  16  feet  or  more,  can  be  erected  today  for  five  and  a  half 
cents  per  cubic  foot  of  contents,  (approximately  $2,100),  figured 
from  the  bottom  of  the  sills  to  the  top  of  the  plate.  To  this  must 
be  added  the  cost  of  the  basement  below  the  sills.  If  concrete,  it 
Avill  cost  from  $5  to  $7  per  cubic  yard  of  concrete,  depending  upon 
the  convenience  of  sand  and  gravel."  He  further  says,  "We  have 
one  near  here  30  by  40  feet  with  12-foot  posts  and  8-foot  basement, 
4  feet  of  which  is  below  the  level  of  the  ground,  which  cost,  in- 
cluding basement,  $1,400." 


242 


TYPES  OF  STORAGE  HOUSES 


It  is  evident  from  the  foregoing  figures  that  the  Maine  type 
of  potato  storage  house  is  a  much  more  expensive  one  tJian  that  of 
the  dugout  or  cellar  type.  But  if  its  durability  is  considered  as 
well  as  the  storage  room  i)rovided  in  the  superstructure,  the  ulti- 
mate cost  of  storage  is  not  so  very  much  greater. 

The  above  figures  are  pre-war  estimates. 

Idaho, — In  the  fall  of  1914,  the  Department  of  Agriculture 
built  a  potato  storage  cellar  at  Jerome,  Idaho,  in  which  some  new 


I 


I 


Fig.  132. — The  more  common  type  of  the  better  class  of  Maine  potato  storage  houses, 
with  rear  end  driveway. 


features  of  interior  construction  were  eml)odied.  The  structure 
is  30  by  50  feet  in  dimensions  with  a  central  driveway.  The  side 
and  end  walls  are  of  concrete,  eight  inches  in  thickness  with  12- 
inch  footings,  and  eight  feet  in  height.  The  even  span  roof  is 
of  wooden  frame  construction,  covered  in  the  usual  way  with  woven 
wire,  straw  and  earth. 

The  interior  arrangement  of  this  cellar  differs  from  that  of  any 
other  noted  in  that  it  is  provided  with  examination  and  disinfect- 
ing rooms,  at  one  end  of  the  cellar  each  approximately  10  by  10 


IDAHO 


243 


feet  in  diameter.  The  balance  of  the  cellar  is  divided  into  eight 
binS;,  four  on  either  side  of  the  driveway,  each  10  by  10  feet.  The 
wooden  floor  of  these  bins  is  a  removable  one,  being  constructed 
in  three  sections,  each  of  which  consists  of  3-inch  strips  of  board 
nailed  to  cleats,  with  1-inch  space  between  the  strips.  These  floor 
sections  are  supported  by  2  by  6  inch  joists  which,  in  turn,  rest 
on  three  4  by  6  sills.  The  2  by  6  joists  were  given  an  inch  shoulder 
on  the  supporting  sills,  thus  providing  a  5-inch  opening  into  the 
driveway,  as  the  joists  are  at  right  angles  to  it  (Fig.  109).  The 
interior  face  of  the  concrete  side  and  end  wall  of  the  storage  cellar 


I'iG.  133. — Potato  stoiago  liousc  trtctt-d  by  the  U.  S.  Dept.  of  Agiicultuie  on  Aroostook 
Farm,  Presque  Isle,  Me.  Note  large  roof  ventilators  or  cupolas.  Small  greenhouse  on  left 
is  used  for  starting  the  seed  potatoes. 

l)roper  is  furred  with  2  by  4  studding,  spiked  to  the  4  by  G  sill  below 
and  to  the  rafters  above.  The  studding  is  spaced  33  inches  apart 
in  the  clear  and  is  covered  to  the  height  of  six  feet,  with  4-inch  boards 
spaced  one  inch  apart.  The  slatted  division  walls  of  each  bin  are 
double  when  in  place.  They  are  constructed  in  sections  similar  to 
the  floor,  and  are  attached  at  each  end  to  supporting  posts.  The 
cleats  on  w^hich  the  4-inch  board  slats  are  nailed  come  opposite 
to  each  other  when  in  place,  thus  insuring  a  2-inch  air  space 
in  the  walls.  This  type  of  floor,  wall,  and  partition  construc- 
tion afi'ords  a  complete  circulation  of  air  around  each  bin,  which  is 
especially  desirable  for  the  storage  of  seed  stock. 
16 


244 


TYPKR  OF  STORAGE  HOUSES 


-C 


I 


QUESTIONS  ON  THE  TEXT  245 

QUESTIONS  ON  THE  TEXT 

1.  What  is  the  most  primitive  type  of  stoi-ageV 

2.  Describe  the  method  of  pitting-  potatoes. 

3.  What  is  a  safe   limit  in  size? 

4.  What  sliould  be  tlie  shape  of  the  pile? 

f).  Why  should  there  be  some  provision  made  for  ventilation? 

fi.  Give  successive  steps  in  the  pitting  of  potatoes. 

7.  What  is  the  advantage  of  the  pitting  system?     The  disadvantage? 

5.  What  factors  govern  the  determination  of  the  right  type  of  a  storage 

house  ? 
9.  Where  is  the  dugout  or  cellar  type  of   storage  house  most  commonly 
employed  ? 

10.  What  are  the  chief  things  to  consider  in  the  location  of  such  a  storage 

house  ? 

11.  Describe  the  construction  of  the  house,  viz.,  the  cellar,  walls,  and  roof. 

12.  What    further    suggestions    are    given    regarding    more    expensive    and 

durable  walls? 

13.  What  modification  in  roof  structure  is  necessary  in  the  liuinid  sections 

of  the  north  central  and  eastern  states? 

14.  What  fiuiction  besides  insulation  does  the  straw  covered  roof  perform? 

15.  ^^'hat  provision   should   be   made   to   exclude   either   heat   or  cold    from 

the  entrance  way? 
IG.  How  is  ventilation  usiuiUy  provided  in  the  storage  house? 

17.  Describe  interior  arrangement  vi  house. 

18.  Describe  a  ventilated  bin 

19.  Where  no   provision    is   made   for   a   driveway   into   the    storage    house 

how  are  the  potatoes  put  into  it? 

20.  Describe    the    insulated    wooden    storage    house.     Where    is    it    usually 

found  ? 

21.  Why  is  the  type  of  storage  house  now  advocated  for  sweet  potatoes  not 

satisfactory  for  Irish  potatoes? 

22.  In  what  way  does  the  Aroostook,  Maine,  type  of  potato  storage  house 

difl'er  from  those  previously  discussed? 

23.  How  is  this  type  of  house  usually  constructed?     Give  sizes. 

24.  How  are  the  basement  bins  usually  filled? 

25.  Of  what  use  is  the  wooden  superstructure? 

26.  To    what    extent    is    artificial    refrigeration    employed    in    the    potato 

storage   house? 

27.  What  advantage  has  it  o\er  ordinary  storage?     Where  most  apparent? 

28.  What  are  the  present  storage  facilities  in  the  South? 

29.  Describe  the  "Cooper  brine  circulation  system?" 

30.  Is   the    Cooper   system    a    satisfactory   one?     Give    arguments    for    and 

against. 

31.  What   is  the  usual  method   of  determining  the   storage   capacity   of  a 

given  basement  or  bin  space? 

32.  Give  the  cost  data  on   the  construction   of  the   cellar   type  of   storage 

hotise  ? 

33.  Does  the  above  cost  estimate  represent  the  present   sum  necessary  to 

construct  such  a  house?     How  would  it  ditt'er? 

34.  Give  Fitch's  cost  estimate  on  an   average  grade  potato  cellar? 

35.  What  was   Schroeder's   estimate   of  cost   of  constructing   a   20   by    100 

feet  storage  house  in  the  Ited  River  Valley? 


246  TYPES  OF  STORAGE  HOUSES 

36.  How  do  King's  and  Howard's  estimates  on  the  Maine  type  of  storage 

house  compare  with  those  of  the  preceding  ones? 

37.  What  new  features  were  introduced  in  the  interior  arrangement  and 

bin  construction  of  the  Jerome,  Idaho,  potato  storage  house? 

QUESTIONS   SUGGESTED  BY  THE  TEXT 

1.  Make  an  estimate  of  the  number  of   local   storage  houi^es  of   each   of 

the   five   types. 

2.  Describe  some  of  these  which  you  have  seen. 

,*{.  Visit  a  cold  storage  plant  in  your  section.     Study  its  advantages  and 

disadvantages  for  potato  storage. 
4.  If  space  is  rented  in  this  house,  calculate  the  cost  per  bushel  for  storage, 
f).  Make   an   estimate    for    constructing   a   liouse,    locally,   of    one   of   the 

types  2,  3  or  4. 

References   Cited 

1.  Fitch,  C.  L.     1910.    Productiveness  and  degeneracy  of  the  Irish  potato. 

Col.  8ta.  Bui.  176:  47,  Nov.,  1910. 

2.  Thompson,  H.  C.     Storing  and  marketing  sweet  potatoes.     [7.  ,S'.  Dept. 

Agr.  Farmers'  Bui.  548:   1-15. 


CHAPTER   XV 
POTATO  DISEASES  AND  THEIR  CONTROL 

The  potato,  like  most  other  agricultural  plants,  has  its  parasites 
which  prey  upon  its  aerial  and  subterranean  parts,  causing  more 
or  less  severe  injury  to  the  plant  itself  and  to  its  resultant  tubers. 
There  are  also  a  number  of  obscure  maladies  affecting  the  potato 
plant  which  as  yet  cannot  with  certainty  be  classed  as  parasitic 
diseases,  or  for  that  matter,  even  as  diseases  in  the  strict  sense 
of  the  word.  These  types  of  potato  troubles  have,  for  the  lack  of 
a  better  understanding  of  them,  by  the  pathologists,  been  designated 
as  physiological  troubles.  There  is,  however,  a  growing  feeling  in 
the  minds  of  some  of  the  leading  pathologists  and  potato  specialists 
that  some  of  these  maladies  will  in  the  end  be  found  to  be  due  to 
parasitic  organisms. 

Losses  Due  to  Diseases. — It  is  impossible  to  estimate  with 
any  degree  of  accuracy  the  annual  losses  sustained  by  the  potato 
growers  of  this  and  other  countries  from  diseases  and  physiological 
troubles  affecting  the  potato  plant.  It  has  been  estimated  that  the 
potato  growers  of  'New  York  State  in  1903  sustained  a  loss  of 
nearly  $10,000,000  from  the  late  blight  alone^^  Losses  of  $100,- 
000,000  are  by  no  means  infrequent,  and  it  may  be  assumed  that, 
if  all  the  facts  were  known,  it  would  show  a  much  larger  loss  than 
the  amount  mentioned.  These  figures  are  sufificient  to  emphasize 
the  great  economic  importance  of  these  diseases,  insofar  as  they 
reduce  the  money  value  of  the  potato  crop  of  the  country. 

DISEASE    CLASSIFICATION.— The    following    classification    of    diseases 
according   to   causes  ivith  preventive  measures   and  remedies   is   sub- 
mitted in   the  hope   that  it  toill   afford  a  convenient   and  ready 
reference  to  the  more  important  diseases  of  the  potato. 

Parasitic  Diseases 

Remedial   and   Preventive   Measures. 
Fungous. 

1.  Early  blight  Spraying   plants   with   Bordeaux    mixture 

2.  Late  blight  for  1  and  2.  Use  of  disease-free  seed  (2). 

247 


248 


POTATO  DISEASES  AND  THEIR  CONTROL 


3. 
4. 

Fiisarium 
Fusariuin 

(a)  F. 

(b)  F. 
(V)   F. 
(d)  F. 
(0)   F. 

wilt 

dry  rot 

cu  711(1  rtii 

radicicola 

oxijsporum 

hijperoxiispnrum 

discolor  var.  siil- 

_ 

phureum 
(f)    F.   f richothcciodcs 
Vortici ilium  wilt 

G. 

IJhizocton 
Common  i 

ia 

scab 

S. 
10.' 

Silver    ^ci 

Wart 

Leak 

irf 

It 

:trlrri<tl. 

11. 

l?lackleg 

• 

12. 
i:?. 
u. 

Soft  rots 
Bacterial 
Streak 

wilt 

I 

II  rd-iiiirroi 

sTo/xr    (irijuiiisiiis. 

16. 

^Mosaic 
Leaf-roll 

tSli)>ic    mold 

17. 

I'owdery 

scab 

Use  of  disease-free  seed.  Soil  sanitation : 
— rotation  of  crops  and  use  of  disease- 
free  land  where  possible.  Remove  all 
wilt  infected  plants  (3)  and  (5).  Care- 
ful handling  of  tubers. 

Disinfection  of  storaji^e  house  and  low 
storajre  temperature,  34°  to  36°  F.  in 
case  of  4    (f). 


Troaiment  of  seed  in  corrosive  subllinalc 
or  formalin  solutions,  preferably  the 
former. 

Lse  of  clean  seed;  soil  sanitation: — rota- 
tion, etc. 

Use  disease-free  seed.  Plant  imnume  vari- 
eties in  case  of  ( 'J ) .  Reduction  of 
mechanical  injuries  of  tubers  and  rejec- 
tion of  all  injured  stock  in  shipments 
in  case  of    ( 10) . 


Treatment  of  seed  in  corrosive  sublimate 
or  formalin  solutions.  Use  disease-free 
seed.     Remove  infected  plants  and  tubers. 

Use  disease-free  seed.  Soil  sanitation:  — 
rotation,  etc.     Remove  infected  plants. 


Use  disease-free  seed.  Control  insect  pests 
Remove  all  diseased  plants. 


Treatment  of  seed  in  corrosive  sublimate 
solution.  Plant  clean  seed  stock.  Soil 
sanitation. 


18.  Spindlin.u' 

19.  Net  necro; 

20.  Curly  dw. 

21.  Tip-burn 

22.  Arsenical 


sprout 

is 

rf 


Non-parasitic  Diseases 

l^se  stron<i;  vifjorous  seed  stock.  Rogue 
out  all   affected   plants   for    18   and   20. 

Conserve  soil  moisture.  Spray  thoroughly 
with  Bordeaux  mixture. 

l^se  lime  in  arsenical  solutions  used  for 
insect  control. 


Parasitic   diseases   are   those   vhich   are   capable  of  invading   healthy   and 

normally  protected  plant  or  animal   tissues.     The  non-parasitic   types 

of  troubles  are  those  which  are  incapable  of  invading  healthy 

and  normally  protected  plant  or  animal  tissues. 


EARLY  BLIGHT 


249 


Early  Blight. — The  early  blight  is  caused  by  a  fungus,  scien- 
tifically known  as  Macrosporium  solani.  The  attacks  of  this  disease 
are  wholly  confined  to  the  foliage  of  the  potato  plant.  In  the  New 
England  States,  the  disease  usually  makes  its  appearance  on  the 
plants  at  a  much  earlid-  dnti-  tlinn  in  tlir  ]\li(l(llc  West. 


Fig.  135. — Potato  leaf  showing  advanced  stage  of  early  blight  infection 

The  economic  importance  of  the  early  blight,  as  judged  by  the 
damage  it  does  to  the  potato  crop,  is  very  considerable.  The 
writer  has  observed  a  field  in  Franklin  County,  Vermont,  that  was 
almost  completely  destroyed  by  early  blight  in  the  latter  part  of 
July.  A  very  conservative  estimate  of  the  reduction  in  yield  from 
this  field  could  not  have  placed  it  at  less  than  50  per  cent.     Jones'* 


250  POTATO  DISEASES  AND  THEIR  CONTROL 

asserts  that  the  losses  incurred  from  early  blight  in  Wisconsin  may 
amount  to  from  10  to  25  per  cent;  while  Coons-  is  of  the  opinion 
that  the  losses  sustained  from  this  disease  iji  i\Iichigan  may  average 
about  25  per  cent.  It  is  evident  from  the  foregoing  statements  that 
when  there  is  a  serious  early  blight  epidemic  the  losses  sustained  are, 
as  a  rule,  much  greater  than  the  average  potato  grower  realizes. 

Symptoms. — The  outward  or  external  evidences  of  the  presence 
of  early  blight  on  potato  leaves  is  first  noted  as  a  dark  brownish 
or  blackish  s])ot  of  oval,  angular  or  irregular  shape  which,  as  it 
develops,  begins  to  show  a  series  of  concentric  rings  which  give  it 
a  rather  characteristic  appearance  (Fig.  135).  When  the  infection 
is  severe,  these  spots  enlarge  and  finally  coalesce  with  each  other 
to  form  larger  and  still  larger  areas  until  finally  the  entire  surface 
of  the  leaf  may  become  infected  and  eventually  wilts,  dies,  and 
drops  off. 

How  Infected. — The  method  of  infection, according  to  Jones,*^'^ 
may  be  either  through  the  stomates  or  directly  through  the  t;uticle. 
Eands^"  states  that  "in  central  Wisconsin,  natural  infection  is 
generally  first  visible  from  June  20  to  July  10  on  the  crop 
planted  April  25  to  May  15,  and  on  the  late  crop,  spots  may  be 
observed  from  the  middle  of  August  on,  depending  upon  three 
factors :  age,  vigor  of  plant,  and  weather  conditions." 

Source  of  Infection. — It  is  thought  by  Rands  {I.e.)  that  the 
source  of  infection  of  the  early  crop  is  from  the  over-wintered  spores, 
and  possibly  from  conidia  produced  by  over-wintered  m3Telium. 

Preventive  Measures  and  Results. — The  only  satisfactory 
preventive  measure  thus  far  known  is  that  of  keeping  the  plants 
thoroughly  sprayed  with  Bordeaux  mixture.  Lutman,**  in  a  sum- 
mary of  19  years  of  spraying,  makes  the  following  statement  regard- 
ing the  fungicidal  value  of  Bordeaux  mixture  when  properly  made 
and  applied :  "It  very  efficiently  protects  plants  from  the  attacks 
of  the  early  and  the  late  blight."  Milward"  found  that  the  early 
blight  could  be  satisfactorily  controlled  by  four  or  more  applica- 
tions of  the  Bordeaux  mixture,  provided  the  first  one  was  made 
not  later  than  August  15.  Jack^  furnishes  additional  evidence  of 
the  possibility  of  controlling  early  blight  with  Bordeaux  mixture. 
Spraying  experiments  over  several  years  showed  annual  increases 
in  yields  of  the  sprayed  plants  over  the  unsprayed  of  from  16  to 
57  per  cent.  Rands  (I.e.  pp.  42-44)  says,  "For  the  early  crop  under 
Wisconsin  conditions,  the  disease  can  be  profitably  controlled  by 


OCCURRENCE  OF  DISEASE  251 

4  to  6  applications  of  the  standard  5-5-50  Bordeaux  mixture.  Com- 
plete control  can  only  be  attained  by  weekly  sprayings,  begun  when 
the  plants  are  6  to  8  inches  high  and  continued  throughout  the 
remaining  period  of  growth. 

"For  the  late  crop,  the  results  indicate  that  3  or  4  applications 
ordinarily  recommended  for  the  control  of  late  blight  will  also 
control  early  blight. 

"Thoroughness  of  application  cannot  be  over-emphasized  in 
spraying  for  early  blight." 

Further  details  concerning  the  early  blight  may  be  secured  by 
consulting  the  references  mentioned  in  this  discussion,  and  also 
those  listed  in  the  bibliography  appended  to  this  chapter. 

LATE  BLIGHT 

The  disease  of  the  potato,  commonly  known  as  late  blight 
(Pliytophthora  infestans),  is  by  far  the  most  destructive  foliage 
disease  affecting  the  potato  crop.  In  certain  seasons  it  is  also  the 
most  destructive  tuber  disease. 

Occurrence  and  Distribution  of  the  Disease. — As  a  rule,  the 
late  blight  is  confined  very  largely  to  the  North  temperate  zone, 
including  the  whole  northeastern  portion  of  the  United  States  and 
Canada.  It  is  also  fairly  prevalent  in  the  Pacific  Coast  sections 
of  the  states  of  Washington  and  Oregon.  It  also  occurs,  though 
hardly  in  epidemic  form,  along  the  whole  Atlantic  coastal  plain 
section,  but  as  a  rule  causes  little  injury  south  of  Maryland,  as  the 
early  crop  of  this  region  ia  usually  harvested  before  the  late  blight 
has  much  opportunity  to  seriously  infect  either  foliage  or  tubers. 
The  late  crop  of  this  section  is  rarely  attacked  by  the  fungus 
because  the  climatic  conditions  are  unfavorable  to  its  development. 
Late  blight  epidemics  are  more  frequent  in  the  Canadian  Provinces 
of  Quebec,  New  Brunswick,  Nova  Scotia,  Prince  Edward  Jsland, 
the  New  England  States,  New  York,  and  certain  portions  of  Penn- 
sylvania, than  in  any  other  portion  of  North  America.  It  is  also 
a  serious  menace  to  the  potato  crop  in  northern  Europe,  including 
the  British  Isles,  where  epidemics  are  of  as  frequent  occurrence  as 
in  North  America.  The  Australian  potato  grower  also  has  to 
contend  \ni\\  the  late  blight.  According  to  Merino,^°  the  potato 
crop  of  Peru  suffered  from  ail  especially  severe  epidemic  of  late 
blight  during  the  years  1867  to  1877. 


252 


POTATO  DISEASES  AND  THEIR  CONTROL 


It  is  evident,  from  the  foregoing  brief  resume,  that  the  late 
blight  is  prevalent  in  practically  all  potato-growing  sections  where 
cool  and  fairly  moist  climatic  conditions  prevail  during  the  latter 
portion  of  the  growing  period. 

Early  History  of  the  Disease. — It  is  jirobable  that  late  blight 
occurred  in  the  potato  fields  of  Peru,  Chili,  Bolivia,  and  other  coun- 
tries iu  tlie  western  ])ortion  of 
Soutli  America,  where  the 
potato  was  undoubtedly  grown, 
long  prior  to  its  introduction 
into  Europe.  In  fact,  the 
inference  is  a  fair  one  that  the 
late  blight  was  introduced  into 
Europe  from  South  America 
l)y  means  of  infected  tubers. 
Two  disastrous  potato  failures, 
due  to  late  1)light  in  Europe, 
are  mentioned  by  Cathcart 
{I.e.  pp.  376,  277)  •  the  first  in 
1795  and  the  second  in  1845- 
46.  The  latter  epidemic  is 
known  to  have  begun  in  1840 
and  reached  its  climax  in 
1845-46. 

Life  History  of  Late 
Blight. — The  life  history  of 
the  late  blight  fungus  has  been 
a  source  of  considerable  con- 
troversy among  scientists  with 
respect  to  the  manner  in  whicli  it  is  carried  over  from  one  year 
to  another.  ]\Ielhus''  states  that  at  least  six  theories  have  been 
advanced  at  various  times  regarding  the  yearly  advent  of  the  disease, 
viz.:  "(1)  That  the  mycelium  lives  over  in  the  soil;  (2)  that  the 
mycelium  is  perennial  in  the  diseased  tuber;  (3)  that  resting  spores 
are  produced  which  function  in  renewing  infection;  (4)  that  the 
mycelium  is  latent  in  the  potato  plant;  (5)  that  the  fungus  fruits 
on  the  parent  tuber  in  the  soil,  and  the  spores  reach  the  surface 
and  cause  infection  of  the  foliage;  and  (6)  that  sclerotia-like  bodies 
or  muco-plasm  give  rise  to  infection."  Melhus  further  states  that 
the  second  theory  is  the  only  one  supported  by  any  amount  of 
experimental  data. 


Fig.   130. — Potato  stem  and  foliage  affected 
by  the  Late  Blight.     Maine  tita. 


LIFE  HISTORY  OF  LATE  BLIGHT 


253 


Assuming  that  the  perennial  mycelium  theory  is  correct,  the 
life  history  of  the  fungus  is  a  comparatively  simple  one.  The 
mycelium  or  the  plant  structure  proper  of  the  late  blight  over- 
winters or  .hibernates  in  the  infected  tubers.  Melhus  says  (I.e. 
p.  99 )  that,  when  infected  tubers  are  used  for  seed  purposes,  "the 
mycelium  grows  from  the  seed  piece  into  the  stem,  where  it  travels 
up  to  the  surface  of  the  soil  and 
sporulates.^'  If  the  weather  con- 
ditions are  favorable  to  the  ger- 
mination of  the  spores,  infection 
of  the  foliage  (Fig.  136)  is 
almost  inevitable;  and  with 
continued  favorable  weather  an 
epidemic  may  develop.  The 
sjiores  formed  are  usually  known 
to  laymen  as  summer  spores ;  the 
])athologist  calls  them  conidio- 
spores.  These  reproductive 
bodies  are  formed  on  the  ex- 
treme tips  of  branched  hypha\ 
or  fruit-bearing  structures, 
which  protrude  througli  tlie  epi- 
dermis of  the  under  side  of  the 
infected  portions  of  the  leaf 
(Fig.  137).  As  each  successive 
spore  is  fully  matured,  it  is  sepa- 
rated from  the  fruit-bearing 
stalk.  When  the  moisture 
and  temperature  conditions  are 
favoral)le  for  the  growth  of  the  late  blight,  the  hyphae  and  resultant 
conidiospores  are  borne  in  such  great  abundance  as  to  give  the 
infected  areas  the  appearance  of  being  covered  with  a  whitish, 
glistening,  felt-like  growth.  When  such  conditions  of  growth  obtain, 
the  spread  of  the  disease  is  very  rapid.  As  each  spore  is  cut  off 
from  its  fruiting  hypha,  it  drops  upon  the  foliage  beneath;  or  it 
may  be  borne  by  currents  of  air  to  adjacent  i)lants  and,  finding 
lodgement  upon  the  upper  surface  of  a  healthy  leaf  it  will,  if 
sufficient  moisture  is  present,  germinate  in  from  two  to  four  hours. 
The  ])rocesi?  of  germination"  is  an  interesting  one,  the  tip  of  the 
spore  opens  and  six  or  more  small  bodies  called  zoospores  are 
thrust  out.    These  bodies  are  naked  masses  of  protoplasm  provided 


Fig.  137. — Characteristic  appearance 
of  Late  Blight  infection  of  potato  leaves. 
Maine  Sta. 


254 


POTATO  DISEASES  AND  THEIR  CONTROL 


with  whip-like  strands,  or  as  they  are  technically  known,  cilia,  by 
means  of  which  they  move  about  in  the  drop  of  water  for  a  short 
time,  after  which  they  come  to  rest  and  push  out  a  slender  germ- 
tube,  which  penetrates  the  epidermal  structure  proper  in  some  cases, 
while  in  others  the  germ-tube  passes  through  the  stomata.  Once 
the  germ-tube  has  penetrated  the  leaf  structure,  it  develops  rapidly 
into  a  mycelium  structure,  which  in  from  two  to  four  days  produces 
fruiting  hyphse. 

The  tubers  are  infected  (Fig.  138)  by  the  fallen  spores,  which 
are  carried  through  the  soil  by  the  aid  of  rain.     Late  bliglit  in 


Fig.  138.— Tubers  affected  with  Late  Blight  rot. 

the  absence  of  other  infection  causes  a  dry  rot  of  the  tuber.  The 
soft  rot  malodorous  decay  of  the  tuber,  following  late  blight 
infection,  is  due  to  non-parasitic  bacteria  which  invade  the  dead 
tissues  caused  by  the  blight  and  rapidly  complete  the  destruction 
of  the  tuber. 

Control  Measures. — It  is  obvious  that  if  the  primary  infection 
each  season  is  due  to  planting  blight-infected  seed  pieces,  the  first 
control  measure  to  be  taken  is  the  rejection  or  exclusion  of  all 
infected  seed  stock,  insofar  as  it  is  humanly  possible  to  do  so.  The 
second  control  measure  is  that  of  protecting  the  foliage  of  plants 
from  late   blight   infection   by  keeping  them   well   covered  with 


CONTROL  MEASURES  255 

Bordeaux  mixture;  this  generally  necessitates  spraying  the  plants 
from  three  to  six  or  more  times  during  the  growing  season.  The 
number  of  sprayings  is,  in  a  large  measure,  dependent  upon  seasonal 
conditions;  if  the  weather  is  favorable  to  the  development  and 
spread  of  late  bliglit,  that  is,  rainy  or  muggy,  and  the  temperature 
not  excessively  high,  more  frequent  sprayings  are  necessary  to  pre- 
vent infection  than  when  the  weather  is  dry  and  hot  as,  under  the 
latter  conditions,  the  late  blight  is  quickly  checked.  It  should  be 
borne  in  mind  that  under  favorable  conditions  for  the  growth  and 
spread  of  late  blight,  it  can  only  be  held  in  check  by  the  most 
thorough  and  careful  spraying.  It  is  not  sufficient  to  simply  go 
over  the  field  with  a  sprayer  carrying  a  pressure  of  75  to  100 
pounds  per  square  inch  and  one  nozzle  to  the  row,  applying  possibly 
50  to  GO  gallons  per  acre.  Such  spraying  will  iiot  control  late 
blight,  and  is  responsible  for  many  criticisms  of  the  efficacy  of 
Bordeaux  mixture  in  the  prevention  of  late  blight. 

The  grower  should  also  bear  in  mind  that  no  amount  of  spraying 
will  save  the  infected  portions  of  the  plant  after  the  fungus  has 
once  entered  its  tissues.  The  Bordeaux  mixture,  or  any  other 
fungicide,  is  a  preventive  and  not  a  remedy  for  blight.  To  suc- 
cessfully combat  this  disease,  it  is  necessary  that  the  foliage  of  the 
potato  plant  be  kept  thoroughly  covered  with  Bordeaux  mixture 
throughout  the  period  in  which  infection  is  most  likely  to  occur; 
but  inasmuch  as  this  period  is  a  variable  one,  depending  on  climatic 
conditions,  it  is  advisable  to  make  the  first  application  when  the 
plants  are  from  six  to  eight  inches  in  height.  The  application  should 
bo  repeated  as  often  as  may  be  necessary  to  keep  the  new  growth,  as 
well  as  the  old,  thoroughly  covered  with  the  fungicide. 

In  the  purchase  of  a  spray  machine,  it  is  important  to  bear  in 
mind  the  following  factors:  (a)  The  durability  of  the  machine; 
all  working  parts  of  the  pump  coming  into  contact  with  the  spray 
liquid  should  be  made  of  brass;  (b)  that  the  pump  should  be  capable 
of  developing  and  maintaining  a  pressure  of  from  150  to  250 
pounds  when  carrying  two  or  three  nozzles  ])er  row;  (c)  that  the 
construction  of  the  pump,  especially  of  the  piston  chambers,  be 
such  as  to  require  a  minimum  amount  of  packing,  and  that  all 
valves  or  chambers  requiring  packing  shall  be  easily  accessible  and 
of  simple  construction.  For  further  information  on  sprayers  see 
Chapter  XVII. 


256  POTATO  DISEASES  AND  THEIR  CONTROL 

rUSARIUM  WILT 

Symptoms  of  Disease. — Tlie  lirst  noticeable  symptom  of  fusar- 
ium  wilt  ill  the  potato  plant  is  a  characteristic  rolling  or  wilting 
of  the  lower  leaves,  followed  in  severe  cases  by  premature  death 
of  the  foliage  and  finally  of  the  whole  plant. 

The  date  at  wdiich  the  above  symptom  first  manifests  the  pres- 
ence of  the  disease  in  the  plant  varies  according  to  the  date  of 
infection.  If  disease  infected  tubers  are  planted,  it  may  )je  evi- 
denced in  an  imperfect  stand  of  uneven-sized  plants.  Generally 
speaking,  wilting  of  the  foliage  does  not  occur  until  the  plants 
are  a  foot  or  more  in  height.  The  wilting  is  due  to  the  invasion 
of  the  ducts  or  water  channels,  through  which  the  leaves  are 
supplied  with  moisture,  by  the  mycelium  of  the  fungus  which  finally 
causes  a  complete  stoppage  of  the  upward  movement  of  water, 
thereby  resulting  in  the  death  of  the  plant. 

In  the  earlier  stages  of  the  disease,  the  lower  leaves  arc  first  to 
wilt.  This  waiting  and  consequent  rolling  of  the  leaves  should  not 
be  confused  with  the  true  leaf-roll.  The  first  symptom  of  fusarium 
wilt  difi'ers  from  the  true  leaf-roll,  in  that  the  wilted  leaves  lack 
turgidity,  whereas  those  affected  with  loaf-roll  are  turgid  to  the 
point  of  brittleness. 

The  foliage  of  wilt  infected  plants  assumes  a  lighter  green  color 
than  that  of  normal  plants  and  as  the  disease  progresses  may,  and 
generally  does,  turn  quite  yellow. 

Causal  Organism. — The  causal  organism  is,  as  has  already 
been  stated,  a  fungus  known  as  Fusarium  oxi/sporwm.  There  are 
two  sources  of  infection  of  the  plant  from  this  disease:  (a)  From 
planting  infected  tubers,  and  (b)  from  fusarium-infected  soil. 
The  fungus  gains  access  to  the  main  stem  of  the  plant  through  its 
rootlets,  and,  possibly  in  the  case  of  infected  seed  pieces,  through 
direct  invasion  of  the  main  stem. 

Occurrence  of  the  Disease. — The  occurrence  of  fusarium  wilt 
seems  to  1)e  regional  rather  than  general.  It  is  prevalent  in  the 
Eed  River  valley  of  Minnesota,  North  Dakota,  Nebraska,  Utah, 
Arizona,  California,  New  York,  and  the  New  England  States.  It 
is,  however,  more  or  less  generally  })revalent  from  New  York,  west 
to  the  Pacific  coast,  and  is  generally  distributed  throughout  Europe. 

Control  Measures. — As  diseased  seed  and  infected  soil  are  the 
two   sources  of   infection,   its   control    is   confined   to   the   use  of 


SPECIES  OF  FUSARIUM  257 

disease-free  seed  and  of  land  which  is  free  or  reasonably  so  from 
the  fusarium  wilt  fungus.  The  first  control  measure  is  easier  of 
execution  than  the  second  one,  as  the  presence  of  the  disease  in 
the  seed  tuber  can  usually  be  detected,  but  there  is  no  practical  way 
of  determining  whether  the  fungus  is  present  in  the  soil  or  not, 
except  through  a  ]irevious  knowledge  of  the  behavior  of  a  potato 
crop  on  that  particular  soil  or  field;  and  there  is,  as  yet,  no  prac- 
tical method  of  disinfecting  the  soil. 

Fusarium-infected  tubers,  at  least  those  in  which  the  disease 
has  made  some  progress,  show  a  brownish  discoloration  of  the  vas- 
cular bundles  at  the  stem  end.  This  discoloration  is  only  detected 
by  clipping  off  a  thin  slice  from  the  stem  end  of  the  tuber.  It  is 
Avell  to  state,  however,  that  not  all  tubers  showing  a  brownish 
discoloration  are  necessarily  infected  with  fusarium  wilt,  as  there 
is  an  internal  bro\\niing  thought  to  be  physiological  which  very 
closely  resembles  the  wilt  disease.  Inasmuch,  however,  as  all  ring 
discoloration  of  the  tuber,  other  than  that  which  is  normal  to 
the  variety,  is  undesirable,  it  is  advisable  to  reject  all  such  tubers 
for  seed  purposes.  All  plants  showing  infection  in  the  field  should 
be  removed  if  the  crop  is  intended  for  seed  purposes.  Careful 
roguing  in  the  field  is,  perhaps,  more  important  than  the  exami- 
nation of  each  seed  tuber  in  the  manner  just  described. 

FUSARIUM    DRY    ROT 

Dry  rot  of  potato  may  l)e  caused  by  one  or  more  of  several 
species  of  Fusaria  whicli  are  known  to  be  parasitic  on  the  tubers 
of  potatoes. 

Forms  of  Dry  Rot. — There  are  a  number  of  forms  of  dry  rot 
such  as,  the  dry  stem-end  rot,  the  j)owdery  dry  rot,  and  a  number 
of  other  forms  which  are  largely  due  to  wound  invasions  by 
the  fungi. 

Species  of  Fusarium. — Carpenter^  claims  that  F.  eumartii,  F. 
ladicicola,  F.  oxysporum,  F.  hyperoxysporum,  and  F.  discolor  var. 
sulphur eiini  have  been  clearly  proven  to  be  parasitic  upon  the 
potato  tuber.  In  addition  to  these,  it  is  known  that  F.  frichothe- 
ciodes  is  responsible  for  heavy  tuber  losses,  due  to  the  "powdery  dry 
rot,"  in  western  Nebraska  and  other  western  states  where  the 
conditions  are  favorable  for  its  development.  According  to 
Carpenter,  {I.e.  p.  '207),  F.  ctniKirfii  is  a  new  stem-end  and  wound- 


258 


POTATO  DISEASES  AND  THEIR  CONTROL 


4,:| 


\ 


./" 


SPECIES  OF  FUSARIUM 


259 


invading  dry  rot  of  the  jjotato  tuber  which  annually  causes  serious 
damage  in  Pennsylvania.  F.  radicicola  is  a  widely  prevalent  dry 
rot  similar  to  F.  eumartii.  It  is  also  responsible  for  the  so-called 
"jelly-end"  rot  of  the  tuber  so  common  in  the  tule  lands  of  San 


Fig.   140.— Potato  plant  atTected  with  Verticillium  Wilt. 


Joaquin  and  Sacramento  Eiver  delta  regions  in  California  (Fig. 
139),  as  well  as  other  irrigated  sections  in  the  Pacific  northwest. 
It  is  commonly  associated  with  F.  oxysporum  in  this  disease.  F. 
oxysporum  and  F.  hyperoxysporum,  which  have  been  commonly 
regarded  as  purely  vascular  tissue  parasites,  have  been  found  by 
Carpenter  to  be  capable  of  entirely  destroying  potato  tubers. 
F.  discolor,  var.  sulphur eum  occurs  in  hollow-hearted  potatoes, 

17 


260  POTATO  DISEASES  AND  THEIR  CONTROL 

causing  decay.  The  infected  ])ortion  oi'  the  tuber  turns  a  sultur 
yellow.  According  to  Carpenter,  it  has  been  isolated  from 
decaying  tubers  from  both  J^orth  and  South  Dakota. 

Preventive  Measures. — Employ  the  same  preventive  measures 
as  were  recommended  for  the  control  of  fusarium  wilt.  Care  in 
the  harvesting  and  handling  of  the  crop  throughout  the  harvesting, 
sacking  and  shipment  of  it  to  market  is  necessary  to  the  end  that 
mechanical  injuries  to  the  tubers  may  be  reduced  to  the  least  jjos- 


Fig.   141. — Plants  in  foreground  affected  with  Vcrtieilliuin    Wilt.     Near  Portland,  Ore. 

sible  percentage.  The  importance  of  observing  these  precautions  can 
only  be"  realized  when  we  remember  that  most  of  the  tuber  decay 
caused  by  these  species  is  due  to  the  invasion  of  the  fungi  through 
bruised  or  cut  tissues.  "  It  has  been  very  clearly  demonstrated  that 
in  the  case  of  the  powdery  rot  caused  by  F.  tncholheciodes, 
practically  all  of  the  infection  is  the  result  of  wound  infections 
by  this  organism.  Tt  has  also  been  clearly  shown  that  thorough 
disinfection  of  the  storage  house,  by  spraying  or  washing  all  interior 
parts  with  a  corrosive  sublimate  solution  or  fumigating  the  house 
with  sulfur  fumes,  is  absolutely  necessary  before  storing  the  new 


SYMPTOMS 


261 


crop.  Fortunately,  careful  studies  have  shown  that  this  fungus 
can  be  held  in  check  by  holding  the  temperature  of  the  storage 
house  at  about  35  to  40  degrees  F. 


VERTICILLIUM    WILT 


Symptoms. — The  outward  symptoms  of  verticillium  wilt, 
{V.  (dho-afrum),  insofar  as  they  are  expressed  by  the  affected 
plants,  are  very  similar  to  those  of  fusarium  wilt  (Figs.  140  to  142). 


-^-'A.-JZ 


'.      4« 


^*^^ 


Fig.   142. — View  shows  conrlitiinj  (.f  jilmil  ^  m   :i  l,,u-    |,ait   i^f   llir   lirl,|;    iiiaiiN    ur;ni   and 
wilting  plants.     Same  field  as  above. 

Orton^*  says:  "Verticillium  wilt  is  often  not  strikingly  different 
from  fusarium  wilt  in  outward  appearance,  though  it  may  induce 
a  more  rapid  wilting.  The  presence  of  the  mycelium  and  vascular 
browning  in  the  upper  portions  of  the  plant  is  indicative  of 
verticillium,  as  fusarium  does  not  usually  extend  into  the  tips  of  the 
stalks.  The  profuse  production  of  conidia  on  the  stalks,  often 
before  they  are  entirely  dead,  is  still  more  characteristic."  It  is 
not  as  prevalent  in  the  United  States  as  in  Europe,  though  in  neither 
country  does  it  cause  as  serious  injury  to  the  potato  crop  as  does 
the  fusarium  wilt.  Unlike  the  latter,  it  seems  to  thrive  best  in 
the  northern  potato-growing  regions. 


262 


POTATO  DISEASES  AND  THEIR  CONTROL 


Preventive  Measures. — The  most  effective  method  of  con- 
trolling the  disease  is  that  of  seed  selection.  Disease  infected  tubers 
show  a  darker  discoloration  of  the  vascular  ring  than  do  those 
infected  with  fusarium  wilt.  Rotation  of  crops  should  also 
be  practised. 

^  EHIZOCTONIA  SOLAN!  OR  BLACK  SCURF 

Economic  Importance. — The  disease  of  the  potato,  botanically 
known  as  Bliizoctonia  soknii,  is  of  vastly  greater  economic  importance 

than  is  generally  recognized  by 
])otato  growers  of  this  and  foreign 
countries.  This  is  partly  due  to 
the  fact  that  a  considerable  por- 
tion of  the  injury  caused  by  this 
disease  is  not  observed,  because 
the  portion  of  the  potato  plant 
attacked  is  beneath  the  surface  of 
the  ground.  To  a  large  extent 
this  unobserved  injury  and  conse- 
quent loss  in  crop  production  is 
sustained  in  the  first  stages  of 
growth  of  the  potato  plant.  The 
extent  of  the  loss  is  dependent 
on  the  degree  of  infection  of  the 
soil,  or  that  of  the  seed  piece 
planted.  The  character  of  this 
loss  is  in  the  infection  and  com- 
plete destruction  of  the  germin- 
ating sprouts  of  the  seed  piece 
])lanted,  resulting  in  missing 
I)lants  which  the  grower  usually 
attributes  to  mechanical  defects 
in  the  operation  of  the  potato 
Maine  sta."    "  planter  used,  or  to  the  lack  of  a 

strong  eye  in  the  seed  piece  itself.  This  statement  is  amply  con- 
firmed in  Figures  143  and  144,  which  well  illustrate  the  manner 
and  character  of  the  injury  inflicted  by  this  fungus. 

Symptoms  and  Causal  Organism. — The  very  serious  fungous 
disease  of  tlie  potato  ])laiit,  Rliizoclonia  solani,  is  quite  commonly 
known  as  Hack  scurf  or  scurf.  This  name  has  been  applied  to  it 
as  a  result  of  the  appearance  of  the  resting  or  sclerotial  stage 


Fk;.  14.3.— Typic  „___ 

octonia  injury.     Note  dead  shoots  at  base. 


example  of  Rhiz- 


METHOD  OF  ATTACK 


263 


of  this  fungus  on  the  surface  of  the  tuber.     The  sclerotial  bodies 

of  the  fungus  resemble  a  dark  brownish  or  blackish  felt-like  mass 

which,  in  general  appearance,  is  not  unlike  small  masses  of  soil 

clinging  to  the  skin  of  the  tuber   (Fig.  145).     These  masses  are 

not  removed  by  washing  but  may  be  scraped  off  without  leaving 

any  visible  injury  to  the  skin 

of  the  tuber.     These  sclerotial 

bodies  are  the  resting  stage  of 

the  fungus,  and  are  a  direct 

means     of     transmitting     the 

fungus  to  the  resultant  crop,  if 

the    infected    tubers    are    not 

treated  in  a  corrosive  sublimate 

solution  before  planting  them. 

During  the  stage  at  which  the 

fungus  is  producing  its  perfect 

spores,    it    is   known    as    Cor- 

ticium  vagum  var.  solani.   This 

stage  in  the  development  of  the 

fungus    usually    occurs    about 

the    middle    of    the    growing 

season  (Figs.  146  and  147). 

Method  of  Attack.— The 
fungus  attacks  all  underground 
parts  of  the  plant.  The  chief 
points  of  difference  between 
this  fungus  and  that  of  the 
fusarium  wilt  is  that  the 
former  attacks  the  outer  por- 
tions of  the  roots,  tuber-bear- 
ing stolons  and  the  main  stem  of  the  plant  beneath  the  surface 
of  the  ground,  and  in  a  large  number  of  instances  completely  girdles 
them.  The  chief  injury  comes  from  the  destruction  of  the  ger- 
minating shoots,  and  the  tuber-bearing  stolons.  These  injuries  are 
direct  and  appreciable,  whereas  the  losses  caused  by  the  destruction 
of  the  smaller  rootlets  or  partial  encircling  of  the  main  stem  are 
difficult  to  estimate.  When  it  causes  severe  injury  to  the  main  stem 
of  the  plant  it  is  usually  evidenced  in  a  more  erect  and  rigid  con- 
dition of  the  terminal  portion  of  the  stem,  the  upper  leaves  of  which 
show  a  more  or  less  distinct  reddish  tinge;  and  in  the  formation 


Fig.  144. — Typical  example  of  Rhizoctonia 
njury  to  tuber-bearing  stolons.    Maine  Station. 


264  POTATO  DISEASES  AND  THEIR  CONTROL 

of  an  abnormally  large  number  of  relatively  small  tubers  on  the 
stem,  just  at  or  beneath  the  surface  of  the  ground. 

Preventive  Measures. — Disinfection  of  the  seed  by  immersion 
in  a  corrosive  sul)limate  solution  of  the  same  strength  and  for 
the  same  period  as  that  recommended  for  common  scab.  Planting 
on  clean  land,  when  it  is  possible  to  do  so,  is  also  advisable, 

COMMON  SCAB 

Causal  Organism, — The  common  scab  of  the  potato  tuber  is 
caused  by  an  organism,  Actinomyces  scabies,  whicli  has  perhaps 


Fig.  145. — Tuber  showing  sclerotial  or  resting  stage  of  Rhizoctonia.  If  such  a  tuber 
was  used  for  seed  purpose  witliout  being  immersed  in  a  corrosive  sublimate  solution-  for  1  y^ 
to  2  hrs.  it  would  infect  the  resultant  crop. 

occasioned  greater  controversy,  as  to  whether  it  should  be  classed 
with  fungi  or  with  bac^teria,  than  that  of  any  other  parasitic 
disease.  The  latest  classification  places  it  in  the  fungi  group  of 
plants.  Unlike  most  other  fungous  or  bacterial  diseases  attacking 
the  potato,  the  common  scab  injury  is  very  largely  confined  to  the 
tuber  and  unless  the  scab  injury  is  severe,  there  is  no  appreciable 
reduction  in  yield. 

Tuber  Injury. — The  chief  injuries  are:    (1)    Tlie  appearance 
of  the  tubers;    (2)   the  slightly  greater  waste  in  preparing  them 


REMEDIAL  MEASURES 


265 


for  table  use;  (3)  the  reduced  yield;  (4)  a  very  direct  monetary 
loss  involved  due  to  the  discrimination  of  the  markets  against 
scabby  tubers ;  (5)  their  unsalability  for  seed  purposes ;  (6)  if  used 
for  seed  purposes,  there  are  likely  to  be  a  great  many  missing  plants 


Fig.  14(5. — Extreme  example  of  tuber  injury  by  Rhizoctonia.     Maine  Station. 

owing  to  the  weakening  or  destruction  of  the  germs  or  buds  of  scab- 
infected  eyes  (Figs.  148  and  149). 

Distribution. — Common  scab  is,  perhaps,  more  Avidely  distri- 
buted than  any  other  disease  of  the  Irish  potato.  Investigations 
by  Pratt^^  have  shown  that  scab  organisms  may  be  present  in 
absolutely  virgin  soil  rather  far  removed  from  that  under  cultiva- 
tion. In  fact,  so  common  is  this  disease  that  it  may  be  said  to 
occur  almost  everywhere  the  potato  is  grown. 

Remedial  Measures. — As  the  scab  organism  can  and  does  live 
over  in  the  scab  pustules  on  the  tuber  from  one  season  to  the  next, 
and  under  favorable  conditions  is  able  to  infect  the  new  crop  of 


266  POTATO  DISEASES  AND  THEIR  CONTROL 

tubers  while  they  are  still  growing,  it  is  advisable  to  disinfect 
all  seed  stock  used  regardless  of  whether  it  is  scabby  or  not.  This 
is  readily  accomplished  by  immersing  the  tubers,  before  they  are 
cut,  in  a  solution  of  corrosive  sublimate  or  of  formalin. 

The  corrosive  sublimate  solution  is  a  more  effective  disinfecting 
agent  for  the  black  scurf  (rhizoctonia)  than  is  the  formalin. 

When  the  soil  in  which  the  seed  is  to  be  planted  is  already 
infected  with  the  scab  organism,  seed  disinfection  is  not  necessarily 
a  guarantee  of  a  disease-free  crop  of  tubers. 

Preventive  Measures. — The  only  preventive  measure  possible 
for  the  individual  grower  to  put  into  practice  is  that  of  adopting 


"> 


OC 


K 


Fig.  147. — Cross  sectiona  of  tubers  affected  with  Rhizoctonia  Maine  Station. 

a  definite  system  of  crop  rotation  and  in  avoiding,  as  far  as  possible, 
the  use  of  land  known  to  be  infected  with  the  scab  organism  for 
potatoes.  In  view  of  the  fact  that  yirgin  soil  may  be  infected 
with  the  scab  organism,  the  use  of  new  land  does  not  offer  an 
absolute  guarantee  of  freedom  from  infection,  though  as  a  rule 
it  does  produce  clean  seed.  Thus  far,  no  practical  method  has  been 
discovered  for  destroying  scab  organisms  in  the  soil.  It  is  known, 
however,  that  a  soil  giving  an  alkaline  reaction  is  much  more 
likely  to  be  infected  with  scab  than  one  that  is  slightly  acid.  Appli- 
cation of  lime  to  soil  intended  for  growing  potatoes  is  not,  there- 
fore, recommended  unless  it  is  known  that  the  soil  is  too  acid  to 


SILVER  SCURF 


267 


permit  of  the  development  of  a  satisfactory  crop,  or  that  it  is  known 
to  be  free  from  scab  infection.  Scab  infection  may  be  controlled 
to  some  extent  by  turning  under  green  rye,  clover,  alfalfa,  or 
other  suitable  green  manuring  crops,  as  the  acidity  in  the  vegetable 
matter  turned  under  tends  to  make  a  slightly  alkaline  soil  neutral 
or  even  slightly  acid.  Heavy  applications  of  fresh  horse  manure 
in  the  spring  before  planting  the  crop  seems  to  aggravate  the  scab 


V---.- 


Fro.  148.— Stem  roots  and  tuhors  sfiowing  common  scab  infection.     Maine  Station. 

when  it  is  already  in  the  soil.  This  is  due  to  the  fact  that  the 
manure  furnishes  an  excellent  growing  media  for  the  potato 
scab  organism. 


SILVER   SCURF 


It  is  supposed  that  tlie  silver  scurf  disease,  Spondylocladium 
atrovirens,  is  of  recent  introduction  from  Europe,  but  it  is  rather 
doubtful  if  this  supposition  is  correct,  as  the  rather  common  inter- 
change of  varieties  between  this   country  and   Great   Britain  in 


268  POTATO  DISEASES  AND  THEIR  CONTROL 

former  years  must  have  resulted  in  the  introduction  of  most  of  the 
less  easily  recognized  diseases  affecting  the  potato  tuber.  Fortun- 
ately, the  disease  known  as  silver  scurf  is  not  a  very  serious  pest 
as  compared  with  many  others. 

Description. — Tubers  infected  with  silver  scurf  first  develop 
dark  spots  or  areas  on  the  surface  of  the  tuber.  These  areas  soon 
begin  to  show  the  fruiting  or  spore-1)earing  hypha?,  which  appear 
to  the  unaided  eye  as  dark  points  or  protrusions.     Under  favorable 


Fig.  149. — Tuber  badly  disfigured  with  common  scab. 

conditions,  sucli  as  heat  and  moisture  in  the  storage  bin,  the  newly 
develoi)ed  spores  may  cause  fresh  infections.  The  fungus  seems ■ 
to  injure  the  skin,  and  possibly  the  cells  beneath,  to  a  sufficient 
extent  to  cause  a  more  rapid  loss  of  moisture,  resulting  in  slightly 
sunken  areas.  The  skin  loses  its  normal  color  and  takes  on  a  silvery 
cast,  thus  giving  to  the  fungus  the  name  of  silver  scurf. 

Preventive  Measures. — Seed  treatment  appears  to  be  ineffec- 
tive, hence  the  only  preventive  measure  possible  is  that  of  the  uf-o 
of  disease-free  seed. 


POTATO  WART  DISEASE  269 

POTATO  WAET  Dlf^EASE 

The  occurrence  of  this  disease,  Chrysophlyctis  endobiolica,  was 
first  noted  in  North  America,  in  October  1909,  by  Gussow,^  the 
Dominion  botanist  of  Canada,  who  recognized  its  presence  on  some 
specimens  of  tubers  sent  to  him -for  identification  from  a  locality 
in  Newfoundland.  Its  occurrence  in  the  United  States  was  first 
recognized  by  Professor  J.  G.  Sanders,  of  the  Pennsylvania  Depart- 
ment of  Agriculture,  at  Harrisburg,  to  whom  infected  tubers  were 
sent  from  Highland,  Pennsylvania,  in  September  1918."  A  careful 
survey  of  this  region,  immediately  after  the  recognition  of  its 
presence,  resulted  in  finding  it  in  twenty-six  towns  and  villages  in 
lower  Luzerne  County.  It  now  seems  probable  that  the  disease 
was  introduced  into  this  mining  section  of  Pennsylvania  through 
the  importation  from  Euro])e  of  twelve  carloads  of  German  grown 
potatoes  in  1913.  More  recently  it  has  been  found  in  some  mining 
towns  in  West  Virginia  and  Maryland.  It  was  originally  described 
in  Hungary  in  1896. 

Description. — The  wart  disease  of  the  potato  is  caused  by  one 
of  the  lower  orders  of  fungi.  It  attacks  all  underground  portions 
of  the  plant,  but  more  especially  the  tubers.  Infection  of  the  tubers 
is  usually  through  the  eye.  The  first  visible  symptoms  of  infection 
are  the  presence  of  tiny  wart-like  growths,  which  rapidly  enlarge  in 
size  until,  in  severe  cases,  the  tuber  is  literally  converted  into  a  huge 
mass  of  warty  excrescences,  which  bear  little,  if  any,  resemblance 
to  a  potato.  In  such  instances,  and  even  where  infection  is 
less  severe,  the  tuber  is  valueless  for  table  purposes.  The  parasite 
reproduces  itself  by  means  of  minute,  yellow-covered,  globular 
bodies  called  sporangia.  These  sporangia  are  born  in  great  num- 
bers just  beneath  the  surface  of  the  wart.  The  summer  sporangium 
is  surrounded  by  a  thin  wall,  while  that  of  the  resting  or  winter 
sporangium  is  quite  thick.  The  former  germinate  as  soon  as 
mature,  and  the  spores  produced  thereby  may  infect  other  portions 
of  the  same  plant.  On  the  other  hand,  the  resting  sporangia  may 
remain  inactive  for  a  long  period,  probably  several  years. 

Each  germinating  sporangium  releases  a  large  number  of 
microscopic,  free-swimming  spores  which  move  about  in  the  soil 
water.  If  these  bodies  fail  to  come  in  contact  ^vith  developing 
potato  tubers,  or  tender  portions  of  the  plant  which  they  are  capable 
of  penetrating,  they  die. 


270  POTATO  DISEASES  AND  THEIR  CONTROL 

Preventive  Measures. — The  only  effective  preventive  measures 
known  are  those  of  planting  disease-free  seed  on  non-infected  soil; 
growing  other  crops  on  wart-infected  land;  or  the  employment  of 
disease-resistant  varieties.  Fortunately  for  the  potato  industry, 
in  wart-infected  districts  there  are  a  number  of  commercial  vari- 
eties of  potatoes  that  appear  to  be  entirely  immune  to  the  disease. 
Investigations  thus  far  have  indicated  that  varieties  of  the 
Irish  Cobbler  group,  and  \nth  one  exception,  thus  far,  of  the 
Green  Mountain  group,  are  entirely  immune  to  the  wart  disease. 
So  is  Spaulding  No.  4  or  Rose  4.  In  Great  Britain,  rather 
extensive  studies  upon  the  immunity  of  the  leading  commercial 
varieties  to  the  wart  disease  have  been  carried  on  at  Ormskirk, 
Lancashire,  England,  for  the  past  two  seasons,  with  the  result 
that  they  are  now  able  to  recommend  quite  a  respectable  number 
of  wart  immune  varieties. 


Causal  Organism. — The  disease  of  potatoes  commonly  known 
as  leak  is,  according  to  Hawkins,*  probably  caused  by  Pythium 
deharyanum.  In  61  attempts,  Hawkins  succeeded  in  isolating  the 
fungus  from  leak  infected  tubers  a  total  of  49  times.  This  fungus 
was  also  found  to  be  rather  universally  present  in  soil  samples 
taken  from  various  parts  of  the  delta  region,  in  the  vicinity  of 
Stockton,  California;  and  the  ai)plication  of  such  soil  to  mechani- 
cally injured  potato  tuber  tissues  caused  infections,  from  which  the 
organism,  P.  deharyanum,  was  isolated.  No  cases  of  infection, 
either  in  the  field  or  laboratory,  were  observed  when  the  skin  of 
the  tuber  remained  unliroken. 

Action  of  the  Disease  on  the  Tuber. — The  action  of  the 
organism  on  the  tissues  of  the  tuber,  under  favorable  conditions, 
causes  a  rapid  and  practically  complete  breaking  down  of  the  cellu- 
lar structure  of  the  tuber,  and  the  resultant  loss  of  its  liquid  con- 
tents. For  this  reason,  the  disease  has  been  given  the  name  "leak," 
that  is,  the  liquid  contents  leak  out.  In  discussing  the  losses  due 
to  the  disease  in  the  delta  region  of  the  San  Joaquin  River,  Cali- 
fornia, Hawkins  says,  "The  rot  is  manifest  in  hot  weather,  and 
appears  soon  after  harvesting.  As  the  potatoes  in  this  region  are 
sacked  in  the  field  and  practically  all  shipped  immediately,  the 
disease  is,  therefore,  first  evident  in  the  car  or  warehouse.     In 


BLACKLEG  271 

extreme   cases   a  whole   shipment   may   be   so   badly   damaged   as 
to  be  worthless." 

Preventive  Measures. — As  the  disease  is  incapable  of  infecting 
uninjured  tubers,  the  obvious  preventive  measure  to  be  employed 
is  that  looking  toward  a  reduction  of  cuts  and  bruises,  resulting 
from  the  harvesting  and  handling  of  the  crop.  The  universal  prac- 
tice of  the  potato  growers  of  this  section  of  breaking  off  the  knobs 
or  prongy  gro^vths,  so  common  with  the  Burbank,  is  an  undesirable 
one  because  it  offers  an  entrance  point  for  the  fungus.  As  most  of 
the  digging  is  done  by  hand  vnt\\  heavy  five-  or  six-tined  hoe  forks, 
many  tubers  are  injured  by  being  pierced  with  one  or  more  of  the 
prongs,  thereby  inoculating  the  tuber  with  disease.  Such  injured 
tubers  should  not  be  sacked  as  salable  table  stock,  because  the 
chances  are  strongly  in  favor  of  such  tubers  decaying  in  transit, 
and  others  may  become  infected  from  them.  All  cut,  bruised  or 
pierced  tubers  should,  therefore,  be  discarded  as  they  are  being 
sacked  for  market. 

BLACKLEG 

The  bacterial  disease  of  the  potato  commonly  known  as  black- 
leg, Bacillus  phytophthorus,  is  rather  widely  distributed  throughout 
the  potato-growing  sections  of  the  northeastern  United  States  and 
Canada.  So  far  as  known,  the  first  recorded  occurrence  of  this 
disease  was  made  by  JonesP^  in  Vermont,  in  1906.  It  was  noted 
in  a  field  of  Green  Mountain  potatoes  on  the  Station  farm.  The  seed 
used  in  planting  this  field  had  been  purchased  in  Iloulton,  Maine. 

Character  and  Appearance  of  the  Disease. — In  describing  the 
character  and  appearance  of  the  disease,  Morse^^*"  says,  "Plants 
affected  by  blackleg  are  readily  distinguished  in  the  field  by  any 
close  observer,  even  at  a  distance  (Fig.  150).  The  affected 
plants  appear  more  or  less  unthrifty  and  usually  undersized, 
varying  with  the  severity  of  the  attack.  The  branches  and  leaves, 
instead  of  spreading  out  normally,  tend  to  grow  upward,  forming 
a  somewhat  more  compact  top,  frequently  with  the  young  leaves 
curled  and  folded  up  along  the  mid-rib.  Later  they  become  lighter 
green  or  even  yellow,  and  the  whole  plant  gradually  dies.  If  the 
disease  progresses  rapidly,  the  stem  may  fall  over  quite  suddenly 
and  wilt,  vni\\  very  little  previous  signs  of  disease  other  than  the 
upward  trend  of  the  foliage  noted  above. 


272 


POTATO  DISEASES  AND  THEIR  CONTROL 


"The  diagnosis  of  suspected  cases  is  easily  confirmed  by  pulling 
u})  the  aU'ected  plants.  Blackleg,  as  its  name  indicates,  is  charac- 
terized by  a  pronounced  blackening  of  the  stem  below  the  ground, 


Fio.  150.— Potato  plant  affected  with  blackleg.   Maine  Sta. 

usually  running  up  one,  two,  or  even  three  inches  above  the  surface. 
Sometimes,  under  very  favorable  conditions,  i.e.,  continued  wet, 
cloudy  weather,  especially  where  plants  are  growing  on  a  naturally 
moist  soil,  the  inky-black  discoloration  may  follow  up  a  portion 
of  the  stem  for  several  inches  a])ove  the  ground  (Fig.  151).    During 


SOFT  ROTS 


273 


the  active  progress  of  the  disease,  the  invaded  tissues  show  a  soft 

wet  decay Usually,  the  seed  tubers  attached  to  affected  stems 

are  entirely  decayed  by  a  soft  rot  or  have  disappeared  entirely. 

If  young  tubers   have  been   formed 

before  the  complete  invasion  of  the  stem, 
they  are  occasionally  affected  in  the 
same  manner . . .  . " 

The  blackened  area  frequently  extends 
up  the  stem  a  foot  or  more,  or  even  to 
the  extreme  tip  of  the  central  stem. 

Extent  of  Loss  to  Crop. — The  ex- 
tent of  crop  loss  from  blackleg  is  relatively 
small  as  measured  by  late  blight,  rhizoc- 
tonia  or  the  fusaria  diseases. 

Remedial  Measures. — Treatment  of 
seed  in  formalin  or  corrosive  sublimate 
will  destroy  surface  infection  by  spores. 

Preventive  Measures. — Discard  all 
tubers  showing  stem-end  discoloration. 
Remove  all  diseased  plants  and  accom- 
panying tubers,  if  any,  as  soon  as  they  are 
noticed  in  the  field.  Strictly  speaking, 
there  is  little  excuse  for  any  progressive 
potato  grower  having  blackleg  plants  in 
his  potato  field,  as  strict  observation  of 
the  preventive  measures  suggested  will 
result  in  its  elimination,  since,  so  far  as 
known,  the  disease  is  only  transmitted 
tlirough  infected  seed. 

SOFT  KOTS 

The  soft  rots  of  potatoes  are  caused  by 
putrefactive  bacterial  organisms,  of  which 
Bacillus  carotovorus  is  a  good  example. 
Generally  speaking,  these  bacteria  are 
incapable  of  infecting  sound,  healthy 
tubers.  They  may  be  regarded  in  the  general  category  of  wound 
parasites,  or  as  parasites  of  plant  tissues  that  have  been  injured 
through  excessive  moisture  and  heat  combined  which,  literally 
speaking,  asphyxiates  the  living  protoplasmic  contents  of  the  potato 
18 


Fig.  151. — Potato  stem  com- 
pletely destroyed  by  blackleg. 
Maine  Sta. 


274  POTATO  DISEASES  AND  THEIR  CONTROL 

tuber,  thus  causing  a  rapid  breaking  down  of  the  cell  structure, 
which  is  further  hastened  by  the  putrefactive  bacteria.  All  of 
these  organisms  convert  the  flesh  of  the  tuber  into  a  slimy  and 
extremely  ill-smelling  mass  of  matter.  Frequently,  these  putre- 
factive organisms  follow  late  blight  infection  of  the  tubers. 

Preventive  Measures. — The  only  preventive  measures  that  can 
be  suggested  are  those  pertaining  to  soil  sanitation,  such  as  good 
drainage  and  aeration. 

BACTERIAL    WILT 

The  disease.  Bacillus  soJanacearum,  commonly  known  as  bacterial 
wilt,  is  one  that  affects  practically  all  of  the  food-producing  members 
of  the  nightshade  family,  such  as  the  potato,  tomato,  eggplant,  etc. 
Its  occurrence  is  mostly  confined  to  the  southern  United  States. 

Symptoms  of  the  Disease. — The  first  evidence  of  infection 
is  a  sudden  M'ilting  of  the  whole  plant,  or  of  one  or  more  of  its 
steuLs  and  finally  the  whole  plant.  For  a  time  the  wilted 
stems  revive  during  the  night,  but  gradually  they  lose  their 
characteristic  bright  green  color  and  become  shrivelled  and  black- 
ened. An  earlier  examination  of  the  vascular  tissue  of  the  stems 
would  have  shown  a  brownish  discoloration  somewhat  similar  to 
that  caused  by  fusarium  wilt.  The  exudation  of  tiny  drops,  of  a 
dirty  or  yellowish-white-colored  liquid,  from  the  cut  surfaces  of 
the  stem,  identifies  it  as  of  bacterial  origin.  In  the  case  of  the 
potato,  the  discoloration  extends  into  the  roots,  tuber-bearing  stolons 
infecting  the  tubers  and  causing  them  to  decay.  Potato  plants 
growing  on  virgin  soil  are  more  apt  to  become  infected  with  this 
disease  than  those  on  old  soil.  As  a  rule  it  does  not,  in  the  aggre- 
gate, cause  very  much  loss  to  the  potato  crop. 

Preventive  Measures. — Eotation  of  crops,  soil  sanitation,  good 
drainage  and  aeration  will  materially  reduce  infection  from  the 
bacterial  wilt  organism. 

STREAK 

Occurrence. — The  disease  kno\vn  as  "streak''  is  tentatively 
classified  as  of  bacterial  origin,  though  as  yet  the  causal  organism 
has  not  been  determined.  It  is  not  of  widespread  occurrence  in 
commercial  potato  fields;  in  fact,  it  might  be  said  to  be  rather 
uncommon  outside  of  the  large  seedling  collection  of  the  United 
States  Department  of  Agriculture,  where  it  has  occurred,  with  more 
or  less  regularity  and  in  some  instances  severity,  in  certain  hybrid 


STREAK 


275 


-f!»i/^ 


Fig.  152. — Potato  leaf  affected   with  streak.     Note  blackened   veins   and   veinlets. 
(Maine  Sta.) 

seedlings.    It  has  also  been  noted  by  Orton^*^  in  a  field  of  Factors' 
at  Puyallup,  Washington,  in  September,  1914. 

Description. — Orton  describes  streak  as  follows :  "Streak  is  first 
to  be  detected  on  the  upper,  full  grown  leaves  of  the  potato  plant 


276  POTATO  DISEASES  AND  THEIR  CONTROL 

in  the  form  of  elongated  or  angular  spots  following  the  veinlets  and 
invading  the  parenchyma  (Fig.  152).  While  somewhat  more  con- 
spicuous on  the  upper  side,  these  spots  are  also  to  be  seen  on  the 
under  side  as  narrow,  discolored  streaks  along  the  veins.  The  typi- 
cal form  may  very  quickly  be  recognized,  and  distinguished  from 
the  spots  caused  by  early  blight  {Macrosporium  solani) ;  though 
the  more  diffuse  spots  of  the  streak  resemble  slightly  the  macro- 
sporium spots,  particularly  when  the  latter  also  occur  on  the  same 
plants,  as  is  often  the  case. 

"The  destructive  progress  of  the  streak  is  rapid.  Shortly  after 
its  appearance  on  the  leaflets,  as  described,  the  petiole  will  be  found 
affected  and  slightly  discolored  by  longitudinal  streaks.  The  peti- 
ole collapses,  and  the  leaf  then  withers  and  hangs  limp;  or  the 
petiole  breaks  at  the  point  of  attachment  to  the  stem,  and  haugs 
by  a  thread  in  a  dead  and  dried  condition.  Since  it  is  the  full 
grown  leaves  that  are  first  attacked,  there  is,  at  this  stage,  a  circle 
of  dead  leaves  about  a  third  of  the  way  down  from  the  terminal 
shoot,  while  the  latter  is  still  green.  The  hanging  dead  leaves 
are  quite  characteristic  of  the  disease,  while  all  the  characters  men- 
tioned form  a  picture  that  is  quickly  seen  and  well  remembered. 

"A  prominent  characteristic  of  streak  is  the  brittleness  of  the 
affected  parts.  The  leaves  break  off  very  easily  and  the  stem  is 
also  brittle 

"The  stem  begins  to  turn  brown,  and  dies  at  a  point  below 
the  tip.  The  upper  leaves  then  ^dlt  and  die,  and  the  disease 
progresses  downward.  Long  faint  brown  streaks  appear  on  the 
stems  also.  Apparently,  the  discoloration  is  Just  below  the  epi- 
dermis but  not  in  the  vascular  bundles.  These  brown  strips  arc 
not  continuous  from  leaflet  to  petiole,  nor  from  petiole  to  stem. 
There  is  no  discoloration  of  the  vascular  bundles  in  the  lower  part 
of  the  stem  or  root,  nor  are  there  any  other  evidences  of  disease 
at  the  root.  The  several  stalks  in  a  hill  die  separately;  all  stages 
may  be  observed  in  one  hill,  from  the  first  spotting  of  the  leaves 

to  the  quite  dead  stalks No  effect  on  the  tubers  has  been 

found.  The  yield  is  reduced  in  proportion  to  the  time  of  onset 
of  the  disease." 

Preventive  Measures. — The  only  measure  possible  to  take  for 
the  control  ol'  streak  is  that  of  rigidly  removing  all  affected  plants 
as  soon  as  the  disease  is  noticeable.  The  use  of  seed  from  fields 
known  to  be  free  from  this  disease  is  also  desirable. 


SYMPTOMS  OF  THE  DISEASE 


277 


Occurrence. — The  disease  of  the  potato  known  as  Mosaic  is  a 
comparatively  new  one  to  American  potato  growers,  having  been 
first  observed  by  Orton^*  (p.  40)  in  northern  Maine,  in  1913,  but 
was  not  found  in  Wisconsin,  ' 
Minnesota,  Colorado,  a  n  d 
other  western  states  during 
either  1912  or  1913.  Accord- 
ing to  Schultz,  Folsom,  Hil- 
debrandt  and  Hawkins,^'  its 
reported  occurrence  in  21 
states  up  to  1918  showed  con- 
clusively that  its  distribution 
was  rather  general  through- 
out the  United  States.- 

Symptoms  of  the 
Disease. — The  S3^niptoms  of 
the  disease  are  far  more  pro- 
nounced on  some  potato  vari- 
eties than  on  others.  The 
mottled  appearance  of  the 
foliage,  Avhich  characterizes 
this  disease  from  that  of 
others  and  from  which  it 
really  derives  its  name,  is 
marked  in  some  varieties  and 
not  very  noticeably  expressed 
in  others.  For  example,  the 
disease  is  rather  difficult  to 
detect  in  the  foliage  of  the 
Eural  varieties,  while  in  the 
Green  Mountain  and  the 
Triumph  varieties  the  (Maine  sta.) 
mottled  appearance  of  the  leaves  is  strikingly  apparent  (Fig.  153). 
The  mottling  is  due  to  a  reduction  of  chlorophyl  in  localized  areas 
over  the  surface  of  the  leaf,  giving  it  a  mosaic  or  mottled  appear- 
ance. Severely  infected  leaves  become  crinkled  or  rugose,  with 
more  or  less  dead  tissue  along  the  margin  of  the  leaves.  In  the 
advanced  stages  of  mosaic,  the  plants  become  much  dwarfed  in 
both  stem  and  foliage.    While  the  tubers  from  the  mosaic-infected 


Fro.    153.— Plant  affected   with   Mosaic. 


278  POTATO  DISEASES  AND  THEIR  CONTROL 

plants  transmit  the  disease  to  their  progeny,  the  eye  has  been  unable 
as  yet  to  detect  any  symptom  of  the  mosaic  disease  in  the  tuber. 

Character  of  the  Disease. — Recognized  as  a  transmissible  para- 
sitic disease,  but  as  yet,  the  pathologists  have  not  succeeded  in 
isolating  the  causal  organism.  It  is  strongly  suspected  by  some 
that  the  mosaic  disease  is  due  to  an  ultra-microscopic  organism. 
It  is  transmitted  from  diseased  to  healthy  plants  in  the  same 
manner  and  by  the  same  plant  lice  as  in  Mosaic  disease.  It  is  also 
transmitted  through  infected  tubers. 

Effect  upon  Yields. — The  evidence  at  hand  indicates  that 
the  mosaic  disease  does  cause  a  material  decrease  in  yields  from 
that  of  healthy  plants.  Orton  (I.e.  p.  43)  noted  a  difference  in 
yield  between  80  mosaic  Green  Mountain  plants  and  80  healthy 
plants  of  22  per  cent  in  favor  of  the  latter ;  while  Wortley^^  claims 
a  difference  of  over  100  per  cent  between  200  healthy  and  200 
mosaic-infected  Triumph  plants.  Murphy^ ^  secured  data  on  682 
diseased  Green  Mountain  plants  and  a  similar  number  of  healthy 
plants  adjacent  to  the  diseased  ones,  and  found  that  the  yield  from 
the  diseased  plants  was  only  58  per  cent  of  the  healthy  plants.  The 
data  presented  are  sufficient  to  indicate  a  marked  decrease  in  yield 
from  mosaic-affected  plants,  thereby  stamping  the  disease  as  one  to 
which  serious  consideration  should  be  given  by  those  interested 
in  the  welfare  of  the  })otato  industry. 

Preventive  Measures. — Owing  to  the  nature  of  the  disease, 
only  preventive  measures  can  be  employed  in  controlling  or  holding 
it  in  check.  The  first  of  these  is  the  elimination  of  all  infected 
plants  in  the  seed  plot  as  soon  as  they  appear;  the  second  is  that 
of  keeping  the  plants  as  free  from  insects,  particularly  plant  lice, 
as  is  possible;  the  third  is  that  of  isolating  or  procuring  a  mosaic- 
free  strain  of  seed.  As  a  matter  of  fact,  however,  the  real  problem 
is  that  of  securing  a  mosaic-immune  variety  or  strain  of  some  of 
our  present  commercial  varieties. 

LEAF-EOLL 

The  leaf-roll  disease  of  the  potato  has,  until  quite  recently,  been 
regarded  as  a  non-parasitic  type  of  disease.  At  the  present  time,  it 
occupies  about  the  same  position  in  the  minds  of  the  pathologists 
as  does  the  mosaic  disease;  it  is  probably  transmitted  from  diseased 
to  healthy  plants  in  the  same  manner,  though  not  necessarily  by 
the  plant  lice  or  aphids. 

Symptoms  of  the  Disease. — As  its  name  indicates,  the  leaf- 
roll  disease  is  expressed  in  a  rolling  of  the  leaves,  a  dwarfing  of  the 


PREVENTIVE  MEASURES 


279 


plant,  a  yellowing  of  the  foliage,  and  an  upward  rolling  of  the 
leaflets  about  their  midrib.  In  advanced  stages  the  leaves  show  a 
distinct  tendency  to  point  ^^pward,  and  quite  frequently  the  upper 
and  younger  leaves  show  a  more  or  less  distinct  pinkish  or  purplish 
tinge  on  their  lower  margin.  The  lower  leaves  are  usually  more  or  less 
thickened  and  leathery,  and,  when  handled,  make  a  crackling  noise. 
Distribution. — Leaf-roll  is  more  or  less  general  in  the  north- 
eastern portion  of  the  Ignited  States  and  Canada,  and  may  be  found 


(A)  (B) 

Fig.  154. — Effect  of  leaf-roll  disease  upon  tuber  production.  (A) — Healthy  plant. 
(B)— Diseased  plant.     (Photo  by  E.  J.  Wortley.) 

here  and  there  in  Avestern  potato  fields.  In  some  sections  of  the 
East,  it  is  becoming  so  abundant  as  to  cause  concern  on  the  part 
of  those  interested  in  the  production  or  purchase  of  high  grade  seed. 

Effect  upon  Yield. — The  tubers  from  leaf-roll  plants,  at  least 
in  the  more  or  less  advanced  stages,  are  greatly  reduced  in  size, 
and  are  usually  borne  very  close  to  the  main  stem  of  the  plant 
rather  than  on  medium-long  tuber-bearing  stolons  (Fig.  154). 

Preventive  Measures. — The  same  preventive  measures  should 
be  employed  for  the  control  of  leaf-roll  as  in  the  case  of  the 
mosaic  disease. 


280 


POTATO  DISEASES  AND  THiaR  (X)NTROL 


POWDERY  SCAB 

Occurrence. — The  existence  of  this  disease,  Spongospora  suh- 
icrrancn,  was  unknown  in  the  United  States  prior  to  papers  pub- 
lished by  Morse^-  and  Melhus^^  in  1913.  It  was  first  reported  in 
North  America  by  Gussow^^  in  February,  1913.  It  is  impossible 
to  more  than  conjecture  the  length  of  time  powdery  scab 
had  been  present,  in  the  potato  fields  of  Maine  and  the  Maritime 
Provinces  of  Canada,  prior  to  1913.  A  survey  of  northern  ]\Iaine, 
in  1914  and  1915,  disclosed  the  fact  that  it  was  widely  distributed 
in  Aroostook  Count}^,  and,  judging  from  the  virulence  of  tuber 


\ 


/       \ 


.-.     Si 


Fig.  155. — Stem  and  roots  of  potato  plants  affected  with  powdery  scab.     (Maine  Sta.) 

infection  in  localized  areas  and  on  certain  types  of  soil,  one  is  forced 
to  the  conclusion  that  powdery  scab  was  not  a  new  disease  in  that 
region,  except  in  point  of  observance.  Melhus"''  says:  "It  seems 
probable  that  it  was  introduced  with  the  heavy  shipments  of  foreign 
potatoes  in  1911."  The  correctness  of  this  supposition  is  hardly 
borne  out  by  subsequent  observations  regarding  its  rather  wide- 
spread distribution.  Probably  no  other  disease,  outside  that  of  the 
potato  wart,  has  caused  more  widespread  alarm  as  to  the  dire  injury 
it  would  occasion  to  the  crop,  if  vigorous  measures  were  not  takeis 
to  stamp  it  out.  IIa])j)ily,  a  closer  acquaintance  with  this  disease 
has  resulted  in  our  finding  that  the  powdery  scab  only  thrives  under 
exceptionally    favorable    environmental    conditions.     It    does    not 


DESCRIPTION  or  THE  DISEASE 


281 


thrive  in  warm  climates  and,  even  when  scab-infected  and  untreated 
seed  stock  is  planted  in  the  South,  the  chances  are  strongly  in  favor 
of  its  not  showing  any  evidence  of  powdery  scab  infection. 

Distribution. — According  to  Melhus,  Eosenbaum  and  Schultz,'-"^ 
powdery  scab  has  been  found  in  the  following  states:  Maine, 
New  York,  Florida,  Minnesota,  Oregon  and  Washington.  It  is 
also  known  to  occur  in  the  Maritime  Provinces  in  Canada  and  in 
British  Columbia.  Its  general  occurrence  in  northern  and  central 
Europe  and  the  British  Islos  is  well  known. 

Description  of  the  Disease. — The  powdery  scab  disease,  like 
that  of  the  common  scab,  lives  over  in  the  soil.     It  attacks  the 


^^^ 


ft 


H^^^ 


Fig.  156. — Potato  tubers  showing  an  abundant  infection  of  powdery  scab.    (Maine  Sta.) 

subterranean  parts  of  the  potato  plant,  i.e.,  the  stem,  roots,  tuber- 
bearing  stolons  and  tubers  (Figs.  155  and  156).  The  chief  injury, 
of  course,  comes  from  the  tuber  infection,  because  it  reduces  the 
yield  and  renders  the  tubers  more  or  less  unmarketable  for  either 
table  or  seed  stock. 

Infected  tubers  liave  the  appearance  of  being  more  or  less 
covered  with  wart-like  protrusions  from  the  surface  of  the  tuber. 
When  freshly  dug,  the  small,  grayish-white  ajipearing  pustules  of 
the  disease  are  strikingly  apparent  (Fig.  156)  ;  but  later  on,  as 
the  surfaces  of  the  tubers  dry  off  and  tlie  epidermal  covering  of  the 
common  scab,  except  that  the  cup-like  depressions  of  the  powdery 
pustules  becomes  ruptured,  it  more  nearly  resembles  those  of  the 
scab   pustules   are   filled   with   brownish   spores   or   spore   masses. 


282  POTATO  DISEASES  AND  THEIR  CONTROL 

Powdery  scab  also  differs  from  tlie  common  scab  in  that  the  disease 
may  continue  to  be  active  in  storage ;  whereas,  the  common  scab 
is  never  active  after  the  tubers  are  removed  from  tlie  ground.  It 
is  chiefly  disseminated  through  the  planting  of  infected  tubers. 
Other  distribution  agencies  are  spore-containing  receptacles,  such 
as  second-hand  sacks,  barrels  or  baskets  in  which  the  crop  is  gath- 
ered ;  and  lastly,  by  means  of  transporting  infected  soil  by  the  feet 
of  farm  animals,  man,  farm  implements,  etc. 

Preventive  or  Remedial  Measures. — While  it  has  not  been 
definitely  proven  that  the  ordinary  seed  treatment  recommended 
for  common  scab  and  rhizoctonia  is  an  absolutely  effective  remedy 
for  powdery  scab,  there  is  evidence  that  tends  to  indicate  that  such 
treatment  does  more  or  less  completely  inhibit*  the  disease.  The 
principal  methods  of  control  are  preventive  rather  than  remedial. 
They  consist  in  the  selection  and  planting  of  clean  seed,  and  in  the 
practice  of  a  definite  crop  rotation  system. 

SPIXDLIXG    SPROUT 

Description. — As  yet,  there  is  no  direct  evidence  that  the  spind- 
ling sprout  of  the  potato  is  caused  by  either  a  fungous  or  bacterial 
parasite.  Tubers  affected  by  spindling  sprout  produce  numerous 
weak,  needle-like  sprouts,  usually  from  most  of  the  eyes,  instead  of 
a  single,  strong,  vigorous  shoot  as  in  the  case  of  normal  seed  stock. 
Pathologists  and  ph3^siologists  are  not  agreed  as  to  the  cause  of  this 
phenomena.  Various  theories  have  been  advanced,  some  of  the 
more  plausible  being  as  follows:  Spindling  sprout  may  be  the 
result  of  the  tubers  having  developed  during  a  hot,  dry  period  and, 
being  subjected  to  a  high  soil  temperature,  their  vegetative  vigor 
is  seriously  impaired.  Exposure  to  high  storage  temperatures  is 
also  thought  to  be  another  cause.  It  Avould  appear  from  these 
several  theories  that  spindle  sprout  is  simply  an  expression  of 
impaired  vegetative  vigor,  rather  than  the  result  of  some 
causal  organism. 

Preventive  Measures. — Tbe  only  preventive  measures  neces- 
sary are  the  removal  of  all  weak  plants  from  the  seed  plot  and  the 
planting  of  strong  healthy  seed  stock. 

XET  NECROSIS 

Description. — Our  knowledge  of  "net  necrosis"  is  about  on  a 
par  with  that  of  spindling  sprout.  In  fact,  it  is  rather  doubtful 
if  the  cause  of  this  trouble  is  as  well  known  as  that  of  spindling 


OCCURRENCE  AND  DISTRIBUTION  283 

sprout.  It  is  thought  that  Jiet  necrosis  may  be  caused  by  unfavor- 
able growing  conditions  when  the  tubers  are  developing.  Similar 
symptoms  have  been  observed  in  tubers  exposed  to  temperatures 
below  the  freezing  point,  in  other  words,  that  had  been  frosted. 
Tubers  affected  with  net  necrosis  can  only  be  detected  by  the 
removal  of  a  thin  slice  from  the  stem-end  of  the  tuber.  The 
presence  of  radiating  brownish  or  blackish  lines  is  fairly  good  evi- 
dence that  they  are  affected  with  this  trouble. 

Preventive  Measures. — All  seed  tubers  showing  discoloration 
of  the  flesh  at  the  seed  end  should  be  discarded.  Plant  only 
healthy  stock. 

CURLY-DWAKF 

Description. — This  type  of  potato  disease  is  in  many  respects 
quite  similar  in  its  appearance  to  that  of  the  true  leaf-roll. 
Orton^*  (p.  38)  describes  its  appearance  as  follows:  "The  stem 
and  its  branches,  the  leaf  petioles,  and  even  the  mid-ribs  and  veins 
of  the  leaves  all  tend  to  be  shortened,  in  many  cases  to  a  very  marked 
extent,  and  particularly  in  the  upper  nodes  of  the  plant,  so  that  the 
foliage  is  thickly  clustered.  The  diminished  growth  of  the  leaf 
veins,  in  proportion  to  the  parenchyma,  results  in  a  bullate,  wrinkled 
leaf,  often  strongly  curled  downward.  There  seems  also  to  be  a 
tendency  to  form  more  secondary  branches  than  is  normal,  and, 
as  these  remain  short  and  liave  curly  leaves,  the  compactness  of 
the  plants  is  more  striking.  The  stems  are  also  very  brittle. 
The  color  of  the  foliage  in  curly-dwarf  is  typically  a  normal  green, 
except  that  in  very  severe  or  advanced  cases  there  is  a  lighter  green 
or  yellow  color,  sometimes  accompanied  by  brown  or  reddish  flecks 
in  the  leaves  where  the  tissues  are  dying.  Typical  curly-dwarf  is 
readily  distinguished  from  leaf-roll  by  the  wrinkled  or  downward 
curling  of  the  leaves,  the  normal  color  of  the  foliage,  and  the 
firmness  of  the  leaves  which  do  not  lack  turgidity." 

As  might  be  expected,  the  tuber  yield  from  curly-dwarf  plants 
is  very  much  reduced  from  that  of  normal  ones. 

The  nature  of  the  disease,  like  that  of  streak,  has  not  been 
determined.  It  is  thought  by  some  pathologists  to  be  simply  an 
advanced  stage  of  mosaic,  but,  as  yet,  there  is  not  sufficient  evidence 
at  hand  to  fully  confirm  this  supposition. 

Occurrence  and  Distribution. — Owing  to  the  confusion  now 
existing  in  the  minds  of  many  regarding  the  identity  of  mosaic- 
dwarf  and  curly-dwarf  when  they  depart  ever  so  slightly  from  the 
purely  distinctive  characters  of  one  or  the  other,  it  is  difficult  to 


284  POTATO  DISEASES  AND  THEIR  C^ONTROL 

express  an  opinion  as  to  the  general  ])rcvalence  of  one  or  the  other 
type  of  disease  in  a  given  locality.  Orton  is  of  the  opinion  {I.e. 
p.  39)  "that  curly-dwarf  ])lays  a  large  role  in  the  deterioration  of 
potatoes."  The  personal  observations  of  the  writer  would  incline 
him  to  believe  that  curly-dwarf  is  much  more  prevalent  in  the  north- 
eastern portion  of  the  United  States.  In  fact,  typical  curly-dwarf 
plants  are  rarely  noted  in  the  western  states.  It  has  been  more 
or  less  common  among  certain  seedling  potato  strains  in  the 
Department's  collection. 

Preventive  Measures. — The  same  preventive  measures  should 
be  pursued  in  the  control  of  curly-dwarf  as  in  that  of  leaf-roll 
and  other  related  types  of  disease. 


Description. — Tip-burn  is  a  purely  physiological  troul)le,  due 
to  the  failure  of  the  roothairs  of  the  plant  to  furnish  a  sufficient 
supply  of  moisture  to  the  leaves  during  dry,  hot,  windy  and  sun- 
shiny days,  when  the  rate  of  moisture  transpiration  from  the  leaves 
is  greater  than  the  rate  of  supply.  This  causes  a  wilting  and 
burning  of  the  younger  and  more  active  cell  tissues  which  are,  of 
course,  the  extremities  of  the  younger  leaves.  When  this  burning 
or,  more  strictly,  scalding  of  the  leaf  tissue  is  sufficiently  severe, 
the  cell  tissues  are  destroyed — the  tip  of  the  leaf  drying  up.  If 
the  heat  and  drought  is  sufficiently  prolonged,  the  whole  leaf 
may  be  destroyed. 

Control. — The  surest  method  of  preventing  or  minimizing  tip- 
burn  is  by  providing  optimum  conditions  for  the  healthy  and  normal 
development  of  the  potato  plant.  Land  well  supplied  with  organic 
matter,  deeply  plowed,  thoroughly  fitted  and  intelligently  culti- 
vated, so  as  to  induce  deep  rooting  of  the  plants  and  conserve  mois- 
ture, coupled  with  thorough  spraying  of  the  plants  Avith  Bordeaux 
mixture,  furnishes  the  best  insurance  against  injury  from  tip-burn. 

ARSENICAL    INJURY 

Improperly  used  arsenical  poisons  frequently  cause  serious 
injury  to  the  foliage  of  the  potato.  Arsenical  injury  is  frequently 
confused  with  early,  blight.  Both  produce  l)rownish  or  blackened 
more  or  less  irregular  areas  on  the  potato  leaf,  and  also  have  more 
or  less  darkened  concentric;  rings  in  them   (Fig.  157). 


PREVENTIVE  MEASURES 


285 


# 


Fig.  157. — Arsenical  injury  of  potato  foliage;  sometimes  mistaken  for  early  blight.  (Maine  Sta.) 

Preventive  Measures. — Do  not  dust  the  plants  with  straight 
Paris  green.  If  it  seems  desirable  to  use  dry  powdered  Paris 
green,  mix  it  witli  at  least  20  parts  of  land  plaster,  air-slaked  lime 
or  any  other  form  of  finely  divided  dry  lime.  Tf  liquid  applica- 
tions of  Paris  green  are  made,  use  at  least  two  pounds  of  lime 


286  POTATO  DISEASES  AND  THEIR  CONTROL 

to  50  gallons  of  the  liquid.  The  lime  neutralizes  the  free  arsenious 
acid  and  thus  prevents  injury  from  burning.  Other  forms  of 
arsenical  poisons,  which  have  white  arsenic  or  arsenite  of  soda 
as  their  base,  should  be  carefully  tested  for  the  presence  of  free 
arsenious  acid;  neutralize  with  lime  if  necessary. 

QUESTIONS  ON  THE  TEXT 

1.  Name  some  of  the  principal  fungous  parasites  of  the  potato. 

2.  What  is  the  estimated  loss  in  some  seasons,  from  late  blight  alone  in 

the  United  States? 

3.  Into  what  two  groups  or  types  of  diseases  are  potato  troubles  classed? 

4.  What  is  meant  by  a  parasitic  disease? 

5.  What  is  meant  by  a  non-parasitic  disease? 

6.  What  parts  of  the  plant  are  attacked  l)y  early  blight  ? 

7.  How  much  injury   does   the   potato  plant   sustain   from   early   blight? 

Give  various  estimates  cited. 

8.  What  are  the  characteristic  symptoms  of  early  blight  on  the  foliage? 

9.  What  are  the  normal  methods  of  infection? 

10.  How  does  the  disease  pass  the  Winter,  and  whence  the  source  of  new 

infections  ? 

11.  How   early   does  the  disease  make   its   first   appearance  on   the    early 

and  the  late  crop? 

12.  What  preventive   measures   may   be   employed? 

13.  How  does  the  late  blight  differ   from  early  blight? 

14.  Why  is  late  blight  more  destructive  than  early  blight? 

15.  In  what  portions  of  North  America  and  Europe  is  late  blight  prevalent? 

16.  W^hat  is  the  extent  of  its  distribution? 

17.  Give  a  brief  account  of  the  life  history  of  late  blight. 
IS.  What  are  the  conidiospores?     How  are  they  borne? 

19.  How  do  the  conidiospores  infect  the  leaves  of  the  potato? 

20.  How  does  tuber   infection  take  place? 

21.  What  control   measure  may   be  employed  to   lessen  the  prevalence   of 

this    disease? 

22.  What  control  measure  can  be  employed  to  prevent  infection? 

23.  Of  what  importance  is  a  good  sprayer  and  intelligent  application  of 

spray  materials? 

24.  What  kind  of  climatic  conditions  are  favorable  to  late  blight  infection? 

25.  When  should  the  first  application  of  Bordeaux  be  made? 

26.  Describe  the  typical  symptoms  of  fusarium  wilt. 

27.  What  species  of  fusarium  is  responsible  for  the  fusarium  wilt? 

28.  What  are  the  two  sources  of  infection? 

29.  What  are  some  of  the  control  measures  that  may  be  employed? 

30.  How  may   a   large   per   cent,   of    fusarium-infected   tubers    be   rejected 

when  cutting  them  for  planting? 

31.  How  does  the  fusarium  dry  rot  differ  from  fusarium  wilt?     What  are 

the  different  forms  of  dry  rot? 

32.  What  is  the  nature  of  the  injury  caused  by  F.  trichotheciodes?     How 

widely  prevalent  is  it? 

33.  How  does  verticillium  wilt  differ  from  fusarium  wilt?     Describe  it. 

34.  What  preventive  measures  can  be  used? 

35.  Of  what  economic  importance  is  the  disease  known  as  rhizoctonia  or 

black  scurf?     Give  the  nature  of  the  loss. 


QUESTIONS  ON  THE  TEXT  287 

36.  What  are  the  chief  distinguishing  characters  of  plants  infected  with 

rhizoctonia  ? 

37.  What  preventive  measures  are  suggested? 

38.  What  is  the  cause  of  common  scab?     Wliat  is  the  nature  of  its  injury? 

39.  What    remedial    measures    are    recommended    for    its    control?     What 

preventive  measures  ? 

40.  What  is  the  effect  of  turning  under  green  manuring  crops  to  correct 

soil  alkalinitj'? 

41.  What  are  the  distinguishing  characteristics  of  silver  scurf? 

42.  What  is  the  best  preventive  measure? 

43.  When  was  the  potato  wart  disease  first  recognized  in  North  America' 

In  United  States? 

44.  Describe  and  give  the  life  history  of  the  wart  disease. 

45.  What  American  varieties  are  immune  to  the  disease? 

46.  What  causes  the  leak  disease  of  the  potato?     Describe  it. 

47.  What  are  the  most  elfective  preventive  measures? 

48.  What  causes  tlie  blackleg  disease  of  the  potato?     Describe  it. 

49.  What  remedial  and  preventive  measures  are  recommended? 

50.  What  causes  the  soft  rots  of  the  potato? 

51.  Are  the  bacteria  which  cause  soft  rot  parasitic  or  non-parasitic?     Why 

do  you  .say  so? 

52.  What   control   measures   are   suggested? 

53.  What  organism  causes  the  bacterial  wilt  of  the  potato?     Describe  the 

symptoms. 

54.  What  preventive  measures  are  suggested? 

55.  What  is  the  cause  of  "streak"?     How  widespread? 

56.  Describe  the  general  appearance  of  a   streak  infected  plant. 

57.  What  preventive  measures  are  suggested? 

58.  When  was  the  mosaic  disease  first  observed  in  America?     How  general 

is    it?  * 

59.  Give  symptoms  and  nature  of  the  disease. 
CO.  How  is   it  transmitted? 

01.  To  what  extent  does  it  affect  yields? 

62.  What  preventive  measures  are  recommended? 

63.  What  is  the  leaf-roll   disease?     Describe   the   symptoms. 

64.  What  effect  has  it  upon  the  yield? 

65.  What  preventive  measures  are  suggested? 

66.  When  and  where  was  powdery  scab  first  observed  in  North  America? 

In    United    States?     Describe    it. 

67.  What  prevents  its  obtaining  a  foothold  in  the  South?     Give  its  climatic 

preferences. 

68.  What  are  the  common  distributive  agencies  of  the  disease? 

69.  What  preventive  or  remedial  measures  are  suggested? 

70.  What  causes  spindling  sprout? 

71.  What   effect   has   prolonged   storage   upon   the   germination    of    tubers 

and  the  size  of  sprouts? 

72.  What  preventive  or  control  measures  are  suggested? 

73.  What  is  known  about  net  necrosis?     Describe  the  diseased  tubers. 

74.  What  preventive  measures  are  advocated  ? 

75.  How   does    "curly-dwarf"   differ    from    leaf-roll?     Give    symptoms    and 

effect  on  yield. 

76.  Give  distribution  and  preventive  measures. 

77.  What    causes    tip-burn?     Describe    the    injury,    and    give    preventive 

measures. 

78.  Describe  arsenical  injury  and  tell  how  to  avoid  it. 


288  POTATO  DISEASES  AND  THEIR  CONTROL 

QUESTIONS   SUGGESTED  BY  THE  TEXT 

1.  Name  the  potato  diseases  in  order  of  their  most  frequent  occurrence 

locally. 

2.  What  proportion  of  the  local  growers  tukc  measures  to  prevent  common 

scab?     What  measures? 

3.  What  proportion  of  tlie  local  growers  spray  for  late  blight? 

4.  What  pressure  is  used?     How  many  nozzles  to  the  row? 

5.  To  what  extent  is  dry  rot  injurious  locally? 

6.  What  local  losses  have  been  found  due  to  soft  rots? 

7.  What  diseases  seem  to  be  increasing  in  local  importance? 

8.  Collect  specimens  of  as  many  potato  diseases  as  possible. 

References   Cited 

1.  C.\RPEXTER,  C.  W.     Ifll5.     Some  potato  tuber  rots  caused  bv  species  of 

Fusarium.      U.   *S'.   Dept.  Agr.   Jour.   Agr.   Res.   5:    180-209,   Nov. 
I,  1915. 

2.  Cooxs,  G.  H.      mi 4.     Potato  diseases  of  Michigan.     Mich.  ^ta.  Spec. 

Bui.  66:  31,  1914. 

3.  Giissow,   H.   T.      1909.     A   serious   potato  disease   occurring   in  New- 

foundland.    Dom.  Can.  Cent.  Exp.  Farms  Bui.  63:   1-8,  Oct.,  1909. 

3a. 1913.    Powdery  scab  of  potatoes  (Spongospora  svhterranea  (Walb) 

Johnson).     Phytopath,  3:   18-19,  1  pi.,  1  fig.,  1913. 

4.  Hawkins,   L.   A.      1916.      The   disease   of   potatoes   known    as    "leak." 

U.  8.  Dept.  Agr.  Jour.  Agr.  Res.  6:  627-639,  July  24.  1016. 

1917.     Experiments  in  the  control  of  potato  leak.     U.  H.  Dept.  Agr. 

Bui.  577:  1-5,  Sept.  14,  1917. 

5.  Jack,  R.  W^.      1916.     Potato  spraying  experiments  for  the  control   of 

Early  Blight    {Alfernaria  solani).     Rhodesia  Aqr.  Jour.   10:    8.^)2- 
869,  1913;   13:  354-360.  1916. 

6.  Jones,  L.  R.      1912.     Potato  diseases  in  Wisconsin  and  their  control. 

Wis.  Sta.  Circ.  36:  10,  1912. 
6a. 1896.     Various  forms  of  potato  blight,  etc.     Vt.  Sta.  Rpt.   (1895)  : 

72-88,  1896. 
fib. 1906.     The  blackleg  disease  of  the  potato.     Vt.    Sta.   Rpt.    1906: 

257-265. 

7.  KuNKEL,   L.   0.      1919.      Wart   of   potatoes.      (A   disease   now   to   the 

United  States).    TJ.  S.  Dept.  Agr.  Bm:  Pit.  Ind.  C.  T.  and  F.  C.  D. 
Circ.  6:  1-14,  Feb.  6,  1919. 

8.  LuTMAN,  B.  F.     ion.     Twenty  years  spraying  for  potato  diseases,  etc. 

Tt.  ma.  Bvl.  159:  219,  1911. 

9.  Melhxis,  I.  E.     1915.     Hibernation  of  Phytophthora  infestans  of  the 

Irish  potato.     77.  8.  Dept.  Agr.  Jour.  Agr.  Res.  5:   72,  1915. 

9a. '1913.      The   powdery    scab    of    potatoes    {Flpongospora    solani)    in 

Maine.     Science,  n.ser.  38:  1.33,  1913. 

9b. 1914.     Powdery  scab   {Spongospora  suhterranea)    of  potatoes.     U. 

S.  Dept.  Agr.  Bui.  82:  1-16,  April,  1914. 

9c. ,  J.  RosKxnAu^r  and  E.  S.  Schut.tz.     1916.     Spongospora  suhter- 
ranea and  Phoma  tuherosa  on  the  Irish  potato.     TJ.  8.  Dept.  Agr. 
Jour.  Agr.  7?p.s.  7:  214,  1916. 
10.  Merino,  J.  G.     1884     Mentioned  by  the  Earl  of  Cathcart  in  an  article 
on  the  cultivated  potato.     Joiir.  Roy.  Agr.  8oc.  20:  288-289,  1884. 


REFERENCES  CITED  289 

11.  Mir.WARD,  J.  G.      inOO.     Dirc'ftioiis   for  spraying  potatoes.      Wis.   Hta. 

Circ.  Inform.  3,  I'JOO. 

12.  Morse,  W.  J.     l!Ji;i.     I'owdrry  scab  of  2)otatue8  in  llie  Ignited  .States. 

Science,  ii.  ser.  38:  61-62,  1913. 

12a. 1909.      Blackleg.      (A  bacterial  disease  of   the   Irish   potato.     Me. 

t^ta.  Bui.  174:  309-328,  Dec.,  1909, 

13.  MuBPHY,   P.   A.      1917.      The   mosaic   disease    of   potatoes.      Agr.    Oaz. 

Can.  4:  345-349,  1917. 

14.  Orton,  W.  a.     1914.     Potato  wilt,  leaf-roll  and  related  diseases.     U.  8. 

Dept.  Agr.  Bui.  64:  7,  Feb.  12,  1914. 

14a. 1920.     Streak  disease  of  the  potato.     Phytoj)ath,  10:   97-100,  pi.  8, 

Feb.,  1920. 

15.  Pratt,  0.  A.      1918.     Soil  fungi   in  relation  to  diseases  of  the  Irish 

potato  in  southern  Idaho.     U.  8.  Dept.  Agr.  Jour.  Agr.  Bes.   13: 
75-77,  1918. 

16.  Rands,   R.   D.      1917.      Earlv   Blight  of  potatoes   and   related   plants. 

Wis.  Sta.  Res.  Bui.  42:\31,  Aug.,  1917. 

17.  SciiULTZ,  E.  S.,  D.  FoLSOiM,  F.  M.  HiLDEUJRANnT,  and  L.  A.  Hawkins, 

1919.     Investigations  on  mosaic  disease  of  the  Irish  potato.     U.  8. 
Dept.  Agr.  Joitr.  Agr.  Res.  17:  247-273,  8  pis.,  1919. 

18.  Stewart,  F.  C.     1903.     Potato  spraying  experiments  in   1903.     N.   Y. 

(Geneva)  Sta.  Bui.  241:  252,  Dec,  1903. 

19.  WORTLEY,  E.  J.     1915.     The  transmission  of  potato  mosaic  through  the 

tuber.     Science,  n.  ser.  42:  460-461,  1915. 


19 


CHAPTER  XVI 

INSECT  AND  ANIMAL  PARASITES  OF  THE  POTATO 
AND  METHODS  OF  CONTROLLING  THEM 

The  potato  has  numerous  insect  pests  and  at  least  one  that  is 
not  a  member  of  the  insect  famil)'.  These  combined  enemies  of 
the  potato  plant  and  tuber  take  an  annual  toll  of  many  millions 
of  dollars  from  the  potato  crop  alone.  A  goodh^  portion  of  this 
loss  is  due  to  the  failure  of  the  grower  to  sufficiently  protect  his 
crop  from  the  ravages  of  these  pests.  Unfortunately,  however,  a 
considerable  portion  of  the  injury  is  caused  by  insect  or  animal 
pests  rather  difficult  of  control,  such  as  the  flea  beetle,  aphid,  leaf- 
hopper,  tuber-moth  and  eelworm.  These  enemies  of  the  potato 
naturally  divide  themselves  into  different  groups,  according  to 
whether  they  have  chewing  or  sucking  organs,  the  parts  of  the  plant 
they  attack,  and,  in  the  case  of  the  eelworm,  their  method 
of  reproduction. 

Group  classification  of  insect  and  animal  parasites. 

A.  Potato  Insect  Parasites 

/.    Leaf-cheuing  and  mining  inserts. 

1.  Colo,  potato  beetle  Spray  plants  with   arsenical   poisons,   such   as 

2.  Flea  beetle  Paris    <>reen,    arsenate    of    lead,    arsenite    of 

3.  Three-lined   beetle  zinc,  etc. 

4.  Tortoise  beetle 

5.  Blister  beetle 

6.  Tuber  moth — see  sec- 

tion II. 

//.    Stem-  and  tuher-eating  insects. 

7.  Stalk  borer  Crop  rotation,  and  dostriu-tion   of  all   infested 

5.  Stalk  weevil  plants.  ^  „      .      •  f 
9.  Cutworm                                Poisoned  bait;    crop   rotation;    fall   plowing  ot 

10.  White  grub  land. 

11.  Wireworm  ,  .,,      ,  ,  r        -i 

6.  Tuber  moth  Covering    tubers    with    heavy    layer    of    soil. 

Prompt  harvesting  of  crop  when  ripe.  Fumi- 
gation of  storage  house.  Use  of  insect- 
free  seed. 

290 


DESCRIPTION  291 

///.     Sucking   insects. 

12.  Potato  aphid  Spray  with  contact  insecticides. 

13.  Four-lined  leaf-bug 

14.  Leaf  hopper  Spray  with  contact  insecticides  and  with  Bor- 

deaux mixture  as  a  repellent. 

Preventive  and  Remedial  Measures. 

B.  Potato  Animal  Parasites 

IV.     Piercing  and  sticking. 

15.  Eel  worm  Crop  rotation.     Use  of  uninfested  seed. 

COLORADO  rOTATO  BEETLE 

Occurrence  and  Distribution. — According  to  Britton,*  the 
Colorado  potato  heetle,  Leptinotarsa  decemlineata,  Say,  was  unknown 
to  the  potato  growers  of  North  America  prior  to  1855.  About 
that  period  the  frontier  of  potato  growing  reached  the  region  where 
these  beetles  were  native,  and  they  developed  such  a  liking  for 
the  foliage  of  the  potato  plant  that  they  soon  forsook  the  native 
solanums,  on  which  they  had  been  feeding,  and  became  a  serious 
pest  of  this  crop.  It  is  supposed  that  they  crossed  the  Mississippi 
river  about  1864  and  reached  the  Atlantic  seaboard  states  some  ten 
3-ears  later.  As  there  was  then  no  practical  equipment  for  spraying 
plants,  the  potato  grower  was  obliged  to  hand-pick  the  bugs  in  order 
to  prevent  serious  injury  to  the  plants  (Fig.  158).  This  laborious 
operation  was  soon  displaced  by  the  use  of  arsenical  poisons,  of 
which  Paris  green  was  the  most  commonly  employed.  At  first, 
much  of  the  spraying  was  done  by  hand,  by  the  use  of  a  whisk- 
broom  or  wisp  of  straw.  This  crude  method  was  soon  followed  by 
the  hand  pump  with  spray  nozzle  attachment.  The  evolution  of 
the  spray  puni])  has  been  rapid  until,  at  the  present  time,  there  are 
many  highly  efficient  mechanically,  as  well  as  gasoline,  operated 
spray  machines  which  do  effective  work   (Fig.  159). 

Description. — The  adult  potato  beetle  is  about  three-eighths 
of  an  inch  long  and  yellow  in  color,  with  five  black  stripes  running 
lengthwise  on  each  wing-cover  and  a  series  of  black  spots  on  the 
thorax.  One  female  may  lay  from  500  to  1,000  eggs.  The  eggs 
are  of  a  bright  yellow  color,  about  one-thirty-second  of  an  inch 
in  length.  They  are  deposited  in  clusters  on  the  under  side  of 
the  leaves  (Fig.  160)  and  hatch  out  in  about  a  week.  The  larvae 
grow  rapidly  and,  when  nearing  full  size,  consume  a  large  amount 


292 


PARASITES 


Fig.  158. — The  old  and  laborious  nietliod  of  controlling  the  Colorado  potato  bcptle. 


Fig.   l.J9. — The  modern  and  less  laborious  nict  hod  of  controlling  the  Colorado  potato 
beetle.     Courtesy  Batenian  Manufacturing  Co. 

of  foliage.  The  full  grown  larva  is  a  Ptont,  floshy  grub,  with  a 
black  head. and  black  s])ots  over  body  (Fig.  1(51 ).  They  reach 
maturity  in  about  three  weeks,  after  which  they  enter  the  ground 
to  pupate.     Two  to  three  generations  arc  produced  in  a  season. 


DESCRIPTION  AND  LIFE  HABITS 


293 


The  last  generation  passes  the  Winter  in  the  ground,  emerging  as 
a  mature  beetle  early  the  next  season. 

Remedial  Measures. — Wliile  the  potato  beetle  is  a  serious 
enemy  of  the  potato  plant  if  left  unmolested,  it  is,  in  reality,  one 
of  the  most  easily  controlk'd.  As  it  is  a  leaf-eating  insect,  the 
manifest  thing  to  do  is  to  keep  the  foliage  of  the  plants  well  covered 
with  some  form  of  arsenical  poison.     Paris  green,  lead  arsenate 


Fig.   KiO.— Eggs  of  the  Colorado  bcetlp,  twice  the  natural  size.     (Conn.  Sta.) 

and  zinc  arsenite  give  xevy  satisfactory  results  when  used  intelli- 
gently. Arsenical  poisons  may  either  be  applied  as  dust  or  liquid 
sprays.  While  dust  sprays  may  give  very  satisfactory  results,  the 
writer  prefers  to  use  liquid  s])rays.  The  plants  should  l)e  dusted 
or  sprayed  at  about  the  time  the  first  batch  of  eggs  are  hatching  out, 
as  they  are  much  more  easily  poisoned  when  they  are  a  few  days  old. 


THE  POTATO  FLEA  BEETLE 

Description  and  Life  Habits. — The  potato  flea  beetle,  Epitrix 
cucumeris,  Harris,  is  a  small,  Idack,  jumping  beetle,  slightly  over 
one-sixteenth  of  an  inch  in  length  and  about  one  twenty-fourth  of 
an  inch  in  width ;  the  antenna  and  legs  are  yellowish,  but  the  body 
parts,  including  the  head,  wing  covers  and  thorax,  are  jet  black. 


294 


PARASITES 


The  mature  beetle  eats  small  holes  through  the  potato  leaf,  giving 
it  the  appearance  of  being  artificially  perforated  (Fig.  162).  When 
present  in  large  numbers  they  cause  very  serious  injury  to  the 
foliage  and,  as  a  result,  very  materially  lessen  the  yield.  The  beetle 
lays  its  eggs  under   rubbish  on   the   ground.        The   larvae   have 


Fig.  IGl.— Larvae  of  the  Colorado  potato  beetle  at  work.     (Conn.  Sta.) 

slender  thread-like  bodies.  They  feed  on  the  underground  parts 
of  the  plant,  particularly  upon  the  tubers.  I  have  personally 
observed  dozens  of  larvas  partially  burrowed  into  the  tuber.  In 
some  sections,  the  tubers  are  so  seriously  injured  by  the  flea  beetle 
larvffi  as  to  be  unsalable.  The  number  of  broods  varies  from  one 
to  two  according  to  locality.  It  has  been  found  that  by  delaying 
the  date  of  planting,  in  some  sections,  it  is  possible  to  avoid  a  large 
portion  of  the  injury  caused  by  the  first  brood. 


REMEDIAL  MEASURES 


295 


Remedial  Measures. — Although  arsenical  poisons  are  quite 
generally  recommended  by  the  entomologist  for  the  control  of  the 
flea  beetle,  the  writer  is  yet  to  be  convinced  that  poisons  are  an 
eflfective  control  measure.  The  flea  beetles  are  difficult  to  control, 
as  they  usually  work  from  the  lower  side  of  the  leaf  and  do  not 
always  puncture  clear  through  the  leaf;  therefore,  poisons  on  the 
upper  surface  of  the  leaf  are  not  likely  to  find  their  way  into  the 


Fig.  162. — Potato  loaves  severely  injured  by  flea  beetles.     (Maine  Sta.) 

digestive  tracts  of  the  flea  beetle.  The  most  hopeful  measure  of 
control  is  that  of  thoroughly  covering  the  foliage  with  Bordeaux 
mixture.  The  Bordeaux  covered  foliage  seems  to  be  distasteful 
to  the  beetle,  and  in  that  way  serves  as  a  repellent  rather  than  a 
remedy.  A  mechanical  device  for  trapping  the  flea  beetles  was 
tested  at  the  Ohio  State  University,  some  years  ago,  by  Metcalf,^^ 
with  apparent  success.  This  device  consisted  of  a  soap  box  with 
cover,  the  front  end  removed,  nearly  half  of  the  central  part  of 
the  bottom  and  a  good-sized  notch  in  the  lower  side  of  the  rear 
end  cut  away.  The  inside  of  the  box  was  coated  with  tangle-foot, 
and  when  pushed  forward  along  the  row  the  flea  beetles,  jumping, 


296 


PARASITES 


when  disturbed,  were  caught  in  the  sticky  material.  By  mounting 
this  box  on  wheels  and  making  some  minor  changes,  it  caught  flea 
beetles  at  the  rate  of  over  25,000  per  acre.  The  use  of  this  or 
some  similar  device  suggests  the  possibility  of  exercising  a  fairly 
complete  control  of  this  insect  pest. 


THREE-LINED    POTATO    BEETLE 


Description. — The  three-lined  potato  beetle,  Lcnut.  inlineaia, 
Oliv.,  is  yellow  with  three  black  stripes  running  lengthwise  of  its 
body  (Fig.  163).  It  bears  some  resemblance  to  the  striped 
cucumber  beetle  but  is  somewhat  larger,  with  a  constri('tcd  thorax 


Fig.  163. — Three-lined  potato  beetle.  Fig.  164. — Larvae  feeding  upon  leaf,  nat- 

Adulta  on  leaf ,  natural  size.  ural  size.    (Conn.  Sta.) 

marked  with  two  black  dots.  The  eggs  resemble  in  color  those  of 
the  Colorado  beetle,  but  are  smaller  and  more  apt  to  be  deposited 
on  the  mid-rib  of  the  leaf,  instead  of  in  clusters  on  the  laminal 
portion.  Tlie  larvae  diifer  also  from  the  Colorado  beetle  in  their 
habit  of  feeding,  as  they  usiuilly  line  up  in  a  row  on  the  under 
surface  of  the  leaf  and  devour  it  as  they  move  from  tip  to  base  of 
it,  leaving  the  larger  veins  intact  (Fig.  164).  The  larvae  are 
buff  or  tan  colored. 

There  are  two  generations  cacli  year.  Tlie  winter  i.s  passed 
in  the  pupa  stage. 

Remedial  Measures. — The  same  measures  are  used  to  control 
this  pest  as  are  employed  against  the  Colorado  beetle. 


DESCRIPTION 


297 


TORTOISE    BEETLES 


Description. — Tortoise  beetles  are  only  occasionally  enemies  of 
the  potato  plant.  They  are  small  hemispherical  beetles,  with  a 
rather  conspicuous  marginal  flange  somewhat  resembling  the  tor- 
toise in  shape  (Fig.  165).  They  usually  feed  upon  the  wild  morn- 
ing glory  and  sweet  potato,  but  are  sometimes  found  upon  the 


Fio.   165. — Adult  Tortoise  beetles  on  potato  leaf,  natural  size.     (Conn.  Sta.) 

potato.  Britton  {I.e.  p.  110)  says  there  are  at  least  three  species 
ill  Connecticut,  viz.,  Coptocycla  hicolor,  C.  clavata,  and  C.  guttata. 
Bicolor  is  of  a  beautiful  iridescent  gold  color,  often  with  incon- 
spicuous black  spots.  It  is  sometimes  called  the  "gold  bug"  or 
"gold  beetle."  Clavata  and  guttata  both  have  brown  backs  with 
translucent  marginal  flange.  The  dark  portion  in  guttata  is  more 
or  less  interspersed  with  translucent  spots.  Clavata  is  larger  than 
guttata,  and  the  brown  area  is  quite  rough. 


298  PARASITES 

The  eggs  are  laid  singly  on  the  veins  or  stems  of  the  leaves; 
each  egg  is  covered  with  a  small  mass  of  black  excrement.  The 
larvas  are  dull  green,  oval,  with  lateral  projections  or  spines,  and 
feed  on  the  under  surfaces  of  the  leaf.  Their  excrement  is  carried 
on  the  caudal  spines.  Only  one  generation  is  produced  each  season. 
The  adult  beetles  pass  the  winter  in  crevices,  and  appear  on  the 
potato  plants  during  the  month  of  May  in  Connecticut.  The 
injury  to  the  potato  plants  caused  by  these  beetles  is  usually  not 
a  serious  one. 

Remedial  Measures. — They  are  readily  controlled  by  arsenic 
poisons. 

BLISTER  BEETLES 

Description. — Blister  beetles  only  occasionally  feed  upon  the 
potato  plant.  They  are  about  half  an  inch  long  and  about  three- 
sixteenths  of  an  inch  in  width,  and  have  soft  wing  covers  (Fig. 
166).  The  principal  species  are  the  black  blister  beetle,  Epicauta 
pennsylvanica,  DeG. ;  the  margined  blister  beetle,  E.  marginata, 
Fabr. ;  the  striped  blister  beetle,  E.  vittata,  Fabr.;  and  tlie  ash  gray 
blister  beetle,  Macrohasis  unicolor,  Kby. ;  all  of  which  occur  in  great 
numbers  in  certain  seasons.  The  blister  beetles  fed  upon  potatoes 
long  before  the  Colorado  beetle  and  are  sometimes  called  "old- 
fashioned  potato  beetles.^'  They  feed  upon  a  variety  of  plants 
besides  the  potato,  among  which  might  be  mentioned  the  golden 
rod  and  cultivated  aster.  The  larvas  do  not  feed  upon  potato 
foliage  as  do  the  adult  beetles. 

Remedial  Measures. — Being  leaf-eating  insects,  they  may  be 
controlled  by  arsenical  sj)rays. 

rOTATO  8TALK-  AND  STEM-BORERS 

The  stalk-  and  steni-l)orers,  like  the  blister  beetles,  do  not  confine 
their  ravages  to  the  potato  plant  alone;  tomatoes,  corn,  rhubarb, 
sugar  beets,  dahlias,  lilies  and  other  plants  furnish  food  for  the 
larvae  of  these  two  insects. 

Life  History  and  Habits. — The  adult  of  the  potato  stalk-borer 
Papaipema  nilela,  Gn.,  is  a  purplish  gray  moth  having  a  wing 
spread  of  about  one  and  a  quarter  inches  (Fig.  167).  The  eggs 
are  deposited  in  the  stem  of  the  potato  and  the  newly  hatched  larva 


LIFE  HISTORY  AND  HABITS 


299 


begins  tunnelling  through  the  pith  of  the  stem.  The  full  grown 
larva  is  one  and  a  half  inches  long.  It  passes  througli  the  pupal 
stage  in  the  tunnel  made  by  the  larva,  and  remains  in  the  stem 
until  it  emerges  as  a  moth  the  following  spring. 

The  life  history  of  the  potato  stem-borer,  Gortyna  micacea,  Est,, 
is  somewhat  different  from  that  of  the  stalk-borer.     According  to 


_^  i'\G.  166. — Adult  margined  blister  beetles  feeding  on  potato  leavee,  natural  size. 
(Conn.  Sta.) 

Brittain^ :  "The  egg?>  are  laid  by  the  female  moth  during  the  latter 
part  of  August  and  September.  They  are  doubtless  deposited  on 
various  weeds,  thougli  we  have  found  them  only  on  couch  grass. 
They  are  very  small,  pinkish  colored  eggs,  faintly  ribbed,  and  are 
laid  loosely  sometimes  in  rather  large  numbers  on  the  stem  partially 
surrounded  by  the  leaf  sheath.  The  larvse  hatch  out  in  June  and 
make  their  way  to  a  suitable  food  plant,  where  they  bore  a  tiny 


300  PARASITES 

entrance  hole  in  the  stem,  usually  at  the  surface  of  the  ground. 
They  bore  in  the  stem  or  in  the  crown  of  the  plant  until  some  time 
in  August,  and  then  enter  the  ground  where  they  transform  to 
pujxi',  emerging  in  late  x\ugust  or  September  as  adult  moths." 

Occurrence. — The  stalk-borer  is  not  a  serious  pest,  as  it  is 
seldom  found  in  abundance  in  any  locality.  The  distribution  of  the 
stem-borer  is  not  given  by  Brittain,  but  it  is  evidently  fairly  com- 
mon in  Nova  Scotia. 

Preventive  Measures. — As  it  is  impossible  to  reach  the  larv« 
with  arsenical  poisons,  the  only  control  measures  that  can  be 
employed  are  the  destruction  of  the  old  potato  stems  and  all  weeds 


Fig.  167. — Adult  Stalk-borer,  natural  size.     (Conn.  Sta.) 

known  to  be  infested  with  the  hibernating  pupae,  or  that  carry  the 
eggs  of  the  stem-borer.  Eational  crop  rotation  practices  are 
also  helpful. 

POTATO-STALK  WEEVIL 

Occurrence. — The  potato-stalk  weevil,  Trich ohoris  irinotaia. 
Say,  according  to  Fayville  and  Parrot,^''  was  collected  in  Douglas 
County,  Kansas,  in  1873  by  Professor  Snow,  and  was  first  recorded 
by  Popenoe.^^  He  reported  it  as  being  common  in  eastern  Kansas. 
It  was  particularly  abundant  in  1897,  causing  more  or  less  serious 
injury  to  Kansas  potato  fields. 

Habits  and  Life  History. — The  potato-stalk  weevil  like  that 
of  the  borer  is  not  confined  in  ils  food  plants  to  the  potato  alone. 


REMEDIAL  MEASURES  301 

The  horseiiettle,  cocklebur,  jiiuson  weed  and  ground  cherry  are 
common  host  plants  for  this  insect  pest. 

The  adult  is  a  small  snout-beetle,  belonging  to  the  same  family 
of  insects  as  the  plum  cuiculio.  It  is  of  an  ashy-gray  color,  about 
one-fifth  of  an  inch  long  and  is  marked  with  three  black  spots  at 
the  base  of  its  vring  covers.  The  female  deposits  her  eggs  in  the 
stem,  main,  and  secondary  branches,  by  first  cutting  a  slit  about 
one-twelfth  of  an  inch  long  in  which  she  deposits  one  egg.  The. 
same  operation  is  repeated  for  each  egg  deposited.  These  eggs 
hatch  in  from  seven  to  eleven  days,  and  the  small  larva  begins  to 
work  its  way  dowiiAvard  towards  the  root  of  the  stalk.  After 
channelling  down  a  distance,  the  larva  turns  round  and  works 
upward,  enlarging  the  channel  as  it  moves  along.  At  maturity,  the 
larva  averages  from  three-eigliths  to  one-half  of  an  inch  in  lengtli, 
with  a  brown  head  and  dark-colored  mouth  parts.  Tlie  body  Ijears 
a  few  light-colored  hairs.  Tlio  ]-)U])al  stage  lasts  from  about  eight 
to  eleven  days.  The  mature  beetle  remains  in  the  stem  until  the 
following  spring. 

Preventive  Measures. —  i'hnploy  the  same  preventive  measures 
as  for  the  stalk-borer. 


As  a  rule,  cutworms  are  not  a  serious  pest  of  the  potato.  Where 
very  abundant  in  the  soil  they  may  cut  off  a  good  many  of  the 
young  stems,  but  rarely  cause  injury  after  the  j)lant  is  six  to  eight 
inches  higli.  They  usually  cut  the  stem  off  near  the  surface  of 
the  ground. 

Life  History. — Cutworms  are  the  larvae  of  noctuid  motlis  and 
there  are  several  species,  three  or  four  probably  being  responsible 
for  most  of  the  injury.  There  is  but  one  generation  each  year,  the 
moths  emerging  and  the  eggs  being  laid  the  latter  part  of  the 
summer.  The  cutworms  become  partially  grown  before  winter, 
after  which  they  burrow  deeply  in  the  soil  and  remain  there  until 
spring.  Their  chief  damage  is  done  in  tlie  early  spring,  when  the 
vegetable  plants  are  young  and  tender. 

Remedial  Measures. — As  the  cutworm  is  not  a  leaf  eating 
insect  and  lives  almost  entirely  in  tlie  ground,  the  usual  methods 
employed  to  control  leaf  eaters  are  of  no  avail.     The  most  effective 


302  PARASITES 

remedial  measure  is  to  partially  bury  some  poisoned  bait.  A  poi- 
Boned  and  sweetened  bran  mash  scattered  over  the  soil  or  partially 
buried  in  it  will  destroy  large  numbers  of  them.  The  formula 
recommended  by  Britton  {I.e.  p.  112)  is  as  follows: 

Wheat  Bran   5  pounds 

Paris  green  or  white  arsenic    5  ounces 

Lemon    or    orange     1  fruit 

Molasses    1  pint 

Water     7  pints 

Mix  the  dry  poison  and  bran  together,  then  squeeze  the  juice 
from  the  lemon  or  orange  into  the  water,  cut  the  pulp  and  peel 


After  Linville  and 


into  fine  pieces  and  add  them  to  the  water,  after  which  add  the 
molasses  and  stir.  Mix  this  syrup  thoroughly  with  the  poisoned 
bran.  (Young  clover  stems  may  be  substituted  for  the  bran).  Fall 
plowing  the  land  is  also  a  desirable  practice. 


WHITE  GRUBS 


Habits  and  Life  History. — The  natural  food  of  the  white 
grubs,  Lachnosternn,  like  that  of  the  cutworms  and  wireworms,  con- 
sists largely  of  grass  roots,  but  they  also  attack  the  underground 
parts  of  other  plants,  among  which  is  the  potato.     The  chief  damage 


PREVENTIVE  OR  CONTROL  MEASURES 


303 


to  the  potato  by  white  grubs  consists  in  their  consumj^tion  of  por- 
tions of  the  tubers.  When  numerous  enough,  they  may  completely 
destroy  the  whole  crop;  such  an  occurrence  is  very  rare,  however, 
and  only  happens  when  the  crop  is  planted  on  old  sod  land.  White 
grubs  are  the  larvaa  of  the  May  or  June  beetles  (Fig.  168).  The 
life  cycle  of  the  chief  species  requires  three  years  for  its  completion. 
The  female  beetle  deposits  her  eggs  in  the  soil  at  a  depth  of 
from  one  to  eight  inches.     The  young  grubs  feed  on  decaying  vege- 


u  by  wire  worms.     (Conn.  Sta.) 


tation,  but  soon  begin  to  eat  the  roots  of  living  ])lants.  They  are 
most  destructive  to  vegetation  during  the  second  year  of  their 
existence,  but  may  also  cause  serious  damage  to  early  spring  crops, 
the  third  year. 

Preventive  or  Control  Measures. — One  of  the  most  effective 
control  measures  that  can  1)e  employed  is  that  of  crop  rotation. 
Grubs  are  seldom  present  in  land  that  is  handled  on  a  short  rotation 
l)asi8,  say  three  or  four  years,  and  may  generally  be  expected  in 
large  numbers  in  old  sod  land,  or  in  land  that  has  been  allowed  to 
grow  weeds  for  several  years.  Poisoned  bait,  such  as  recommended 
for  cutworms,  may  be  used  on  relatively  small  areas.  All  land  sus- 
pected of  being  infested  with  white  grubs  should  be  plowed  in  the 
fall,  in  order  to  expose  as  many  as  possible  of  the  white  grubs  to 
insect-devouring  birds. 


304 


PARASITES 


WIKEWOKMS 
Life  History  and  Habits. — Wireworiiis  are  ilio  larvir  of  "dick'* 

vr  "sua])"  beetles,  belonging  to  the  family  Elaterida}.  They 
include  several  species  which  feed  upon  cultivated  plants,  most  of 
which  belong  to  three  genera,  Agriotes,  Melanotus  and  Drasterius. 
These  larva}  are  small,  hard,  cylindrical,  and  generally  of  a  tan  or 
reddish-brown  color.  It  requires  from  three  to  five  years  for  the 
wireworms  to  pass  through  their  complete  life  cycle,  all  of  which 
time,  except  their  adult  stage,  is  spent  in  the  soil.  While  it  is  pos- 
sible that  the  wireworms  may  cause  considerable  damage  to  the 


Fig.   170. — Potato  tuber  moth  greatly  enlarged.     (Bureau  of  Entomology.) 

roots  and  lower  j)ortion  of  the  stem  of  the  potato  plant,  the  injury 
is  usually  unnoticed.  The  chief  observable  injury  is  that  caused 
by  the  wireworm  boring  into  the  seed  tuber,  often  entirely 
destroying  it  and,  in  attacking  the  new  tubers,  making  them 
unsalable  and  causing  material  waste  in  preparing  those  that  are 
only  slightly  tunnelled  (Fig.  169). 

Preventive  or  Control  Measures. — The  same  control  measures 
should  l)e  employed  against  the  wireworms  as  those  recommended 
for  white  grubs  and  cutworms. 

THE   POTATO   TUBER   MOTH 

The  potato  tuber  motli,  Plithorima'a  operculella,  Zell.,  was  first 
mentioned  in  literature  by  Captain  H.  Berthon-  in  1855.  Berthon 
stated  that  it  had  proved  very  damaging  to  potatoes  in  Tasmania 
in  1854. 


DESCRIPTION 


305 


Occurrence  and  Distribution. — It  was  first  observed  in  the 
United  States  in  185(),  liaving-  l)een  found  in  San  Francisco,  Cali- 
fornia. In  1873,  Zeller-^  published  the  first  technical  description 
of  the  tuber  moth  which  he  made  from  *  specimens  collected  in 
Texas.  According  to  Graf^^  its  distribution  in  the  United  States 
and  foreign  countries  was  as  follows,  in  1917 :  California,  Texas, 
Florida,  North  and  South  Carolina,  and  Virginia.     The  foreign 


\ 


'^- vZ^-2fc^ 


H 


Fig.   171. — Egg  dusters  of  potato  tubor  moth  deposited  in  and  around  potato  eye. 
(Bureau  of  Entomology.) 

countries  are  Tasmania,  New  Zealand,  Australia,  Algeria,  South 
Africa,  India,  Southern  Europe,  Italy,  France,  Spain,  Canary 
Islands,  Azores,  and  Hawaii. 

Origin. — While  there  is  more  or  less  controversy  regarding  the 
origin  of  the  tuber  moth,  the  bulk  of  the  evidence  would  seem  to 
justify  the  assumption  that  it  is  of  American  origin,  probably  from 
South  America. 

Description. — The  potato  tuber  moth  is  a  small,  gray,  night- 
flying  moth  having  a  wing  expanse  of  a  little  more  than  half  an 
inch  (Fig.  170.)  It  usually  hides  under  clods  or  rubbish  during 
the  day  time.  The  adult  moth  is  comparatively  short-lived.  The 
20 


306 


PARASITES 


male  lives  from  1  to  14  days  and  the  female,  2  to  23  days.  The 
female  lays  her  eggs  on  the  under  side  of  the  potato  leaf,  the  petiole 
of  the  leaf  or  the  stem  of  the  plant.  When  potato  tubers  are  ac- 
cessible, the  eggs  are  also  deposited  on  the  tuber  (Fig.  171).  Gen- 
erally speaking,  however,  as  long  as  the  plants  are  green  and  thrifty, 
the  female  oviposits  on  leaf  or  stem  rather  than  on  tuber.  The 
period  of  egg  incubation  varies  from  5  to  34  days,  depending  on 


Fig.  172. — Injury  caused  by  the  tuber  moth  to  the  leaves  and  tips  of  shoots  of  the 
potato  plant.     (Bureau  of  Entomology.    U.  S.  Dep't  of  Agriculture.) 

season  of  year  and  temperature.  The  newly  hatched  larvae  seldom 
move  about  but  commence  at  once  to  mine  into  leaf,  stem  or 
tuber,  as  the  case  may  be.  Those  on  the  leaves  eat  through  the 
epidermal  structure  and  proceed  to  mine  between  the  upper  and 
lower  epidermal  layers  of  the  leaf  (Fig.  172).  They  may  tunnel 
down  the  petiole  into  the  stem  of  the  leaf  or  may  confine  their  min- 
ing operations  entirely  to  the  leaf  blade.  Larvae,  hatched  from  eggs 
deposited  in  the  eyes  or  cracks  of  tlie  tuber,  at  once  begin  burrow- 
ing into  the  tuber  (Figs.  173  and  174).  The  larvse  feeding  period 
ranges  from  14  to  69  days.     The  longer  period  usually  occurs  in 


PREVENTIVE  AND  REMEDIAL  MEASURES  307 

the  storage  house  at  low  temperatures.  The  period  of  pupation 
varies  from  8  to  56  days  (Fig.  175).  Larvae  feeding  on  the  plant 
usually  pass  the  pupal  stage  in  curled  or  rolled  up  leaves,  those  in 
the  stems  partially  protruding  from  old  burrows,  while  others  pupate 
under  clods  or  rubbish. 

Amount  o£  Injury. — The  amount  of  injury  caused  to  the 
potato  crop  by  the  tuber  moth  is  directly  dependent  upon  the 
prevalence  of  the  insect  and  the  way  in  which  the  crop  is  handled. 
As  a  rule,  the  injury  caused  to  the  plant  itself  is  not  serious,  though 


Fig.    173. — Tuber  injured  by  the  larvse  of  the  potato  tuber  moth   Phthorimsea 
operculella.     (Bureau  of  Entomology,  U.  S.  Dept.  of  Agriculture.) 

under  certain  conditions,  they  might  very  materially  reduce  the 
yield.  The  chief  injury  ordinarily  comes  from  tuber  infestation. 
The  larvse  burrow  through  the  flesh  of  the  tuber,  rendering  it 
unsalable.  When  infested  tubers  are  stored  and  not  fumigated, 
heavy  losses  follow.  Thus  far,  the  potato  tuber  moth  is  only  a  seri- 
ous pest  of  the  potato  in  California,  In  other  localities  in  the 
United  States,  it  has  usually  been  associated  with  other  plants,  such 
as  the  tomato,  eggplant  and  tobacco. 

Preventive  and   Remedial  Measures. — The  best  preventive 
measures  to  emjDloy  in  combating  the  tuber  moth  are    (1)   soil 


308 


PARASITES 


sanitation;  (2)  crop  rotation;  (3)  protection  of  tubers  by  ridging 
up  soil  over  them;  (4)  the  prompt  harvesting  of  the  crop  as  soon 
as  it  is  ready  to  dig;  (o)  the  gathering  of  the  tubers  as  soon  as 
possible  after  digging  them.  Soil  sanitation  consists  in  the  re- 
moval and  destruction  of  all  unsalable  potatoes  as  soon  as  the 
marketable  crop  is  gathered.     Crop  rotation  is  always  desirable. 


Fic.   174. — Section  of  a  potato  tuber  showing  larva  and  pupae  of  the  potato  tuber 
moth.     (Bureau  of  Entomology,  U.S.  Dept.  of  Agriculture.) 

Tuber  infection  may  be  materially  lessened  by  slightly  ridging  the 
soil  over  the  tul)ers.  This  ])ractice  prevents  the  female  moths  from 
reaching  the  tubers.  The  prompt  harvesting  of  the  crop  before 
the  vines  are  fully  dead  lessens  the  chances  of  tuber  infestation,  as 
the  moth,  ordinarily,  prefers  to  lay  eggs  on  the  plant,  rather  than 
on  the  tubers;  as  soon,  however,  as  the  vines  are  dead,  the  eggs 
are  laid  on  the  tubers  if  they  are  within  reach  of  the  female  moth. 
It  is  desirable  to  gather  the  tubers  as  quickly  as  possible  after  they 


POTATO  APHIDS 


309 


are  dug,  because  the  disturljed  moths  fly  about  even  during  davlight, 
and  oviposit  on  the  newly  harvested  tubers. 

If  the  tubers  are  known  to  be  infested  by  larvae  or  to  carry  eggs, 
they  should  be  fumigated  as  soon  after  putting  them  in  tlie  storage 
house  as  possible, 

POTATO  APHIDS 

There  are  at  least  two  distinct  kinds  of  aphids  or  plant  lice 
that  cause  more  or  less  injury  to  the  potato  crop.  These  two  aphids 
are  known  scientifically  as  Mucrosiphum   solanifolii,  Ashm.;  and 


I 


Fig.  175. — Larvae  and  pupa  of  the  potato  tuber 
of  Entomology,  U.S.  Dept.  of  Agriculture.) 


loth  greatly  enlarged.     (Bureau 


Myzus  (Rhopalosiphum.)  persica',  Sulzer.  The  first  is  commonly 
known  as  the  pink  and  green  plant  louse,  on  account  of  portions 
of  some  broods  being  pink  and  others  green.  The  second  is  known 
as  the  green  peach  or  spinach  aphid.     These  plant  lice  belong  to  the 


310  PARASITES 

class  known  as  sucking  insects;  that  is,  tliej-  live  upon  the  juices  of 
their  host  plant,  which  they  suck  from  it  b}^  inserting  tlieir  beaks 
into  its  tissues.  In  1917  and  1918,  potato  aphids  were  quite  gener- 
ally prevalent  throughout  the  whole  northeastern  potato-growing 
section  of  the  United  States,  causing  an  untold  amount  of  damage 
to  the  crop.  In  some  localities  they  were  so  abundant  thiit  they 
actually  sucked  out  so  much  of  the  juices  of  the  potato  plant  as  to 
cause  a  premature  ripening  with  a  consequent  material  lessening 
of  the  crop  yield.  In  1919  and  1920,  they  were  not  so  abundant  and 
little  damage  resulted.  In  1907,  Dr.  Edith  M.  Patch^'^  reported 
a  serious  outbreak  of  plant  lice  on  potatoes  in  Aroostook  County, 
Maine,  during  the  seasons  of  1904,  1905  and  1906.  Apparently, 
therefore,  these  periodic  recurrences  of  the  potato  aphid  are  the 
result  of  the  rise  and  fall  of  its  parasitic  enemies  of  which  it  has 
a  numl)er. 

The  rather  recent  discovery  that  the  mosaic  disease  of  the  potato 
is  transmitted  from  diseased  to  healthy  plants,  througli  tlie  agency 
of  these  two  plant  lice,  serves  to  still  further  emphasize  the  neces- 
sity of  controlling  or  combating  these  insect  pests  by  every  known 
practical  method. 

Life  History  of  These  Two  Plant  Lice. — The  pink  and  green 
plaiit  louse  over-winters  in  the  egg  stage.  In  the  Spring,  the  egg 
hatches  and  produces  what  is  known  as  the  "stem  mother."  This 
insect,  in  from  10  to  12  days'  time,  begins  to  produce  living  young, 
all  of  which  are  gravid  females  and  capal)le  of  producing  new 
batches  of  similar  living  young  in  about  the  same  period  of  time 
as  the  "stem  mother."  The  rapidity  of  this  process  of  multipli- 
cation is  best  understood  from  some  observations  made  at  the  Ohio 
Station,  in  which  a  single  aphid  of  this  species  was  caged  on  an 
uninfested  plant.  At  the  end  of  12  days,  her  progeny  (daughters 
and  grand-daughters)  totalled  76,  five  of  which  were  already  pro- 
ducing young.  It  requires  little  imagination  to  picture  tlie  rapidity 
of  the  increase  from  this  point  on.  Most  of  the  broods  produced 
during  the  season  are  wingless  (Figs.  176  and  177),  but  there  are 
occasional  winged  broods.  The  winged  broods  migrate  much  more 
rapidly  than  tlie  wingless  ones,  and  they  are  generally  referred  to 
as  the  migrant  forms.  Toward  the  close  of  the  season,  a  brood 
of  males  and  females  is  produced.  After  mating,  the  female  lays 
a  few  rather  large  eggs,  usually  on  rose  1)ushes,  if  they  grow  in 
the  locality,  and  thus  they  complete  their  life  cycle. 


LIFE  HISTORY  OF  POTATO  APHIDS 


311 


The  green  peach  or  spinach  aphids  usually  over-winter  in  the 
egg  stage.  In  a  mild  climate,  where  succulent  vegetables  such  as 
spinach,  cabbage  or  kale  continue  growth  throughout  the  winter, 
there  is  a  constant  succession  of  broods.     As  a  rule,  however,  the 


Fig.  176. — ^Potato  aphids  on  under  side  of  the  leaves,  natural  size.     (Conn.  Sta.) 

winged  broods  of  aphids  migrate  to  the  peach  or  plum  tree  during 
the  autumn  and  there  the  females  deposit  their  eggs.  In  the  spring 
these  eggs  hatch  out,  and  from  thence  on  the  method  of  reproduction 
is  similar  to  that  of  the  pink  and  green  louse,  except  that  the  first 
few  generations  live  on  the  juices  of  the  peach  or  plum  tree,  after 


312 


PARASITES 


which  they  migrate  to  a  large  number  of  other  plants,  of  which 
spinach  and  the  potato  are  good  examples. 

Remedial  Measures. — As  plant  lice  are  sucking  insects  it  is 
necessary  to  employ  contact  insecticides  to  destroy  them.     liack  of 

■  success  in  the  con- 
trol of  the  plant 
louse  is  largely  due 
to  failure  to  spray 

sufficiently  early  in 

.sJ|L  WK^B     IJjMmL.^  ^^^  season.  In  fact, 

^l^f^^^PUSi    J^^^Sl  ^^  ^'^^^  roses  or  cul- 

tivated ones  occur 
in  the  locality,  the 
first  step  in  the  con- 
trol of  the  pink  or 
green  louse  is  to 
destroy  these  plants 
and  the  peach  and 
plum  trees  before 
the  eggs  hatch; 
or  else  thoroughly 
spray  them,  while 
still  dormant,  with 
a  lime  sulphur  solu- 
tion to  destroy  the 
eggs;  or  a  later 
spraying,  when  the 
"stem  mother"  first 
hatches  out,  with  a 
nicotine  or  kerosene 
emulsion  solution. 
The  destruction  of 
the  early  broods  is 
the  key  to  their  con- 
trol. If  these  earlier 
precautions  are  not  taken,  a  careful  watch  should  be  kept  of  the 
plants  for  the  first  appearance  of  the  aphids  in  order  to  insure 
spraying,  before  they  become  so  numerous,  and  so  well  ensconced  on 
the  under  side  of  the  leaves  as  to  make  it  difficult  to  reach  them  with 
spraying  materials.     A  proprietary  nicotine  sulphate  compound, 


Fia.  177. — Potato  aphids  on  the  tip  of 
A  favorite  feeding  ground.     (Maine  Sta.) 


growing  shoot. 


REMEDIAL  MEASURES 


313 


..  V  ■.•.,«» 


314  PARASITES 

known  as  black-leaf  No.  40,  is  generally  considered  one  of  the 
most  convenient  and  effective  contact  insecticides.  A  well  made 
kerosene  emulsion  solution  is  regarded  by  some  as  more  effective, 
provided  it  is  well  applied.  Failure  to  get  good  results  from  the 
sprays  is  very  often  due  to  the  inefficient  application  of  them. 
A  good  power  sprayer  carrying  a  pressure  of  from  175  to  250  pounds 
per  square  inch  and  two  or  three  nozzles  to  the  row,  so  adjusted 
as  to  spray  the  under  as  well  as  the  upper  side  of  the  foliage,  is 
necessary  to  effectively  control  the  aphids.  It  is  desirable,  when  the 
plants  are  large  and  the  foliage  heavy,  to  attach  a  device,  in  the 
shape  of  a  drop  rod,  to  the  rear  of  the  spray  machine,  but  in  front 
of  the  spray  boom  for  the  purpose  of  bending  over  the  tops  of 
the  plants,  thus  making  it  possible  to  spray  the  under  side  of  tlie 
foliage.  By  slipping  a  larger  rod  over  the  rigid  one  of  sufficient 
size  so  that  it  will  roll  on  it,  the  injury  to  the  foliage  caused  by 
brushing  the  plants  over  will  be  very  materially  minimized.  Direc- 
tions for  the  use  of  spray  materials  -svill  be  found  in  Chapter  XVII. 

THE   FOUK-LINED  LEAF-BUG 

Life  History. — The  four-lined  leaf-bug,  Poecilocapsus  lineatus, 
Fabr.,  is  only  an  occasional  pest  of  the  potato  plant.  According 
to  Britton,*  it  lays  its  eggs  on  the  soft  tender  stems  of  the  currant, 
and  doubtless  other  plants,  about  the  first  of  July,  in  Connecticut. 
The  eggs  are  long  and  slender,  somewhat  curved,  and  are  crowded 
together  in  clusters  of  six  or  eight,  pushed  endwise  into  the  soft 
pith.  These  eggs  do  not  hatch  out  until  the  following  May.  The 
newly  hatched  insects  first  attack  the  tips  of  the  stems  and  the 
young  tender  leaves.  They  suck  out  the  green  pulp  from  the  under 
side  of  the  leaves,  causing  roundish,  semi-transparent  spots  which 
often  coalesce  (Fig.  178).  As  insects  increase  in  size,  larger  areas 
are  involved,  until  the  leaf  turns  brown,  and  dies.  The  nymphs 
at  first  are  bright-red,  marked  with  black  spots,  but  they  soon 
change  to  bright  orange-yellow.  They  pass  through  five  stages  of 
development  in  al)Out  three  weeks  and  wlien  mature,  are  winged, 
nearly  one-third  of  an  inch  in  length,  bright  greenish-yellow  in 
color  with  four  black  stripes  running  lengthwise  on  thorax  and 
wing  covers  (Fig.  178). 

Remedial  Measures. — Spray  plants  with  same  materials  as 
were  recommended  for  the  potato  aphids. 


LIFE  HISTORY  OF  LEAFHOPPER  315 

THE   POTATO   LEAFHOPPER 

Occurrence  and  Injury  Caused. — While  the  potato  leafhopper 
Einpoasca  iiiali  was  originally  described  by  Le  Baron  in  1853  as 
injurious  to  fruit  trees  in  Illinois,  it  has  since  been  found  that  it 
also  feeds  on  many  other  field  and  truck  crops.  In  1896,  Osburn^" 
mentioned  it  as  being  injurious  to  potatoes  in  Iowa.  Twelve 
years  later,  Gibson^ ^  records  similar  observations  regarding  its 
injuriousness  to  the  potato  crop  at  Ottawa.  BalP  (1918)  was  the 
first  observer  to  call  attention  to  the  possibility  of  the  leafhopper 
being  responsible  for  some  of  the  injury  heretofore  called  "tip- 
burn."  He,  in  fact,  is  inclined  to  the  opinion  that  this  insect  causes 
a  specific  infection  similar  in  many  respects  to  that  transmitted 
to  the  leaves  of  beets  by  the  beet  leafhopper.  Ball  has  classified 
the  foliage  injury  caused  by  the  leafhopper  as  "hopperburn,"  in 
contradistinction  to  the  term  "tip-burn"  under  which  all  burning 
of  the  foliage,  outside  of  that  caused  by  arsenical  poisons,  has  here- 
tofore been  known.  In  this  connection  he  says  (1919,  p.  150)  : 
"It  seems  probable  that  a  considerable  amount  of  the  injury  re- 
ferred to  as  'tip-burn,'  in  the  past,  has  been  due  to  the  leafhopper. 
On  the  other  hand,  there  are,  no  doubt,  other  causes  of  the  burning 
of  the  foliage,  and  it  will  be  one  of  the  problems  of  the  future  to 
differentiate  these  factors." 

Description. — The  adult  leafhopper  is  a  pale  green  insect 
about  one-eighth  of  an  inch  long  with  wings  that  fold  over  the 
back.  The  nymphs,  or  immature  forms,  are  wingless  (Fig.  179). 
Both  are  very  active  and  jump  or  fly  away  on  the  slightest  distur- 
bance. The  adults  are,  of  course,  the  more  active  on  account  of 
their  being  able  to  fly. 

Life  History. — The  leafhoppers  pass  the  winter  in  the  adult 
stage  hidden  beneath  weeds  and  other  rubbish,  and  appear  in  the 
spring  when  they  deposit  their  eggs.  BalP  says  (1919,  p.  153)  : 
"The  adults  flying  in  the  spring  at  the  time  the  early  potatoes  come 
up,  laid  their  eggs  in  the  stems  and  mid-ribs  of  the  leaves."  Euggles 
and  Graham,^'*  X)n  the  other  hand,  say  that  they  do  not  usually 
make  their  appearance  on  the  potatoes  until  late  June,  when  the 
adults  lay  eggs  on  the  stems.  This  may  be  true  with  respect  to 
the  late  potato  crop,  but  it  can  hardly  apply  to  the  early  crop,  as 
their  date  of  appearance  must  be  considerably  earlier.  The  eggs  are 
deposited  in  a  longitudinal  or  transverse  slit  in  the  tender  tips  of 


316 


PARASITES 


the  shoots  or  the  mid-ribs  of  the  leaves.  They  soon  hatch  out, 
and  the  wingless  nymphs  begin  at  once  to  suck  the  juices  of  the 
plants  and  reach  maturity  in  about  a  month.  During  this  period 
the  nymphs  cast  their  skins  five  times.  They  usually  feed  on  the 
under  side  of  the  leaf  where  it  is  difficult  to  reach  them  ^nth  contact 
insecticides  (Fig.  179).  Two  broods  of  leaf  hoppers  are  produced 
during  the  season;  the  first  one  appears  in  June,  and  tlie  second 
one  about  August  1. 

Description  of  the  Injury. — BalP  (1918  p.  98)  descril)es  the 
injury  as  follows :  "The  first  appearance  of  injury  differs  slightly 


Fig.  179. — Leaf  hoppers  (Empoasca  mali)  on  potato  leaf.  (Dr.  E.  D.  Ball,  Iowa  Sta.) 

in  the  different  varieties  and  varies  also  with  the  number  of  insects 
and  whether  they  are  in  the  nymph  or  adult  stage.  In  certain 
varieties,  the  leaves  appear  to  curl  uj)  slightly  before  any  burning 

appears The  first  sign  of  trouble  is  usually  a  triangular  area 

at  the  tip  of  the  leaf,  running  back  on  tlie  mid-rib.  This  is  quickly 
followed  by  a  progressive  burning  of  the  margin,  usually  from  the 
ti])  backwards,  but  occasionally  in  more  or  less  triangular  spots 
appearing  along  the  margin,  each  one  of  these  centred  in  a  lateral 
veinlet.  Tliese  increase  in  area  and  the  burnt  margin  increases 
in  width  until  nothing  but  a  narrow  strip  along  the  mid-rib  remains 
green  and,  in  serious  cases,  this  weakens  and  dies  and  tlie  leaf 
shrivels  up. 

"In  practically  all  cases,  it  will  be  ol)served  that  the  burning 
extends  farther  along  the  mid-rib  and  the  lateral  veinlets  than  it 


AMOUNT  OF  INJURY 


317 


does  on  the  membrane  of  the  leaf.  A  further  examination  will 
show  that  these  veins  and  veinlets  are  badly  distorted  by  punctures 
and  usually  shrivelled  and  collapsed  for  some  distance  back  of  an 
apparent  injury.  In  many  cases,  it  will  be  found  that  an  egg 
deposited  transversely  across  the  mid-rib  just  back  of  the  triangular 
spot  at  the  tip  was  res})onsible  for  the  collaj)se  of  this  structure 


\t.. 


\ 

) 


Figs.  180  and  181. — Tubers  infested  with   eelworms. 

and  the  consequent  death  of  the  triangle  at  the  tip."  Ball  {I.e. 
p.  79)  draws  the  following  distinctions  between  tip-burn  and 
hopi^erburn :  "On  leaves  of  different  plants,  where  no  insect  agency 

was   apparently  present it  was   observed  that   the   burning 

appeared  to  affect  the  membrane  of  the  leaves  and  to  avoid  the 
mid-rib  and  veinlets;  while  hopperburn  appeared  first  on  the  vein- 
lets,  and  spread  later  to  the  area  of  membrane  which  they  supplied." 
Amount  of  Injury. — While  it  is  very  difficult  to  estimate  the 
amount  of  injury  to  the  potato  crop,  as  a  result  of  leafhopper 
attacks,  it  is  safe  to  say  that  when  these  insects  are  abundant  they 


318 


PARASITES 


very  materially  lessen  the  yield.  In  some  fields  of  both  early  and 
late  potatoes,  observed  by  the  writer  in  1919,  the  indications  were 
that  the  yield  had  been  reduced  fully  50  per  cent. 

Remedial  and  Preventive  Measures. — As  the  leafbopper  is  a 
sucking  insect,  the  same  remedies  should  be  used  in  combating  it 
as  those  suggested  for  the  pink  and  green  aphids,  viz.,  nicotine 
sulfate  or  kerosene  emulsion,  and  the  same  thoroughness  of 
application  is  necessary  to  get  even  fair  results.  The  leafhopper 
being  such  an  active  insect,  hopping  or  Hying  away  on  the  slightest 


Fig.  182. — Tubers  badly  infested  with  eelworms. 

disturbance,  is  more  difficult  to  destroy  than  is  the  potato  aphid. 
The  best  preventive  measure  is  secured  through  keeping  the  plants 
well  covered  with  Bordeaux  mixture.  The  mixture  serves  as  a 
repellent  to  the  insect  by  rendering  the  foliage  distasteful  to  it. 

THE  EELWORM  DISEASE 

Among  the  many  parasites  of  the  potato  the  eelworm  or  nema- 
tode, Heterodem  radicioln,  is  one  of  the  most  interesting.  It 
is  an  animal  parasite  which  lives  upon  the  juices  of  the  host 
plant  infested.  It  attacks  many  members  of  the  vegetable  king- 
dom, among  which  is  included  the  potato.  Thus  far,  it  has 
caused  greater  injury  to  the  potato  crop  in  certain  portions  of 
California,  Nevada,  Texas,  Florida,  and  the  South  Atlantic  States 
as  far  North  as  Virginia,  than  in  other  localities.  It  has  a  rather 
wide  distribution  in  the  warmer  portions  and  lighter  soils  of 
the  South. 


LIFE  HISTORY  OF  THE  EELWORM 


319 


Description  of  the  Injury. — The  presence  of  eelworms  in  the 
potato  crop  may  be  detected  from  the  general  appearance  of  the 
roots  and  tubers  of  the  plant.  Eoots  that  have  been  invaded  by 
the  eelworni  are  almost  certain  to  have  well-developed  knots  or 
enlargements,  and  the  surface  of  the  tubers  will  be  more  or  less  dis- 
figured by  pimply  or  wart-like  developments,  (Figs.  180  to  182), 
depending  upon  the  severity  of  the  attack.  It  is  quite  possible  to 
mistake  these  pimply  growths  for  those  caused  by  the  larvee  of  the 


Fig.  183. — Photographs  taken  through  the  microscope  of  three  stages  in  the  develop- 
ment of  the  eelworm  which  affects  the  potato.  (A)  An  egg  which  contains  a  young  coiled 
eelworm  or  larva  enlarged  185  times.  (B)  A  larva  at  the  same  magnification.  It  is  in  this 
stage  that  the  eelworms  penetrate  the  roots  and  tubers  of  the  plants.  (C)  A  matured,  pear- 
shaped  female  enlarged  about  25  times. 

flea  beetle.  The  only  way  by  which  the  two  can  be  certainly 
identified  is  by  an  examination  of  the  tissue  of  these  growths;  if 
they  are  caused  by  the  eelworm,  the  white,  glistening,  pear-shaped 
bodies  of  the  mature  female  will  be  noted;  (Fig.  183  c)  whereas, 
if  caused  by  flea  beetle  larvte,  only  dead  vegetable  tissue  will 
be  observed. 

Life  History  of  the  Eelworm. — According  to  Byars,^  "there 
are  three  readily  recognizable  stages  in  the  life  histoi*y  of  this 
eelworm,  or  as  it  is  more  commonly  known,  nematode;  namely. 


320  PARASITES 

the  egg,  larvae,  and  adult  (Fig.  183).  Only  tlie  adults  are  visil)le 
to  the  naked  eye."  The  newly  hatched  hirva3  escape  into  the  soil, 
seek  the  underground  portions  of  the  plant  stem,  roots  or  tubers, 
penetrate  them  and  once  within,  develop  into  tlie  adult  stage. 
After  the  mating  of  the  males  and  females,  the  former  soon  die. 
The  females  remain  in  the  host  tissue,  and  are  capable  of  laying 
large  numbers  of  eggs  which,  in  turn,  give  rise  to  another  generation 
of  larvffi,  thus  completing  the  life  cycle. 

Preventive  Measures. — Serious  injury  to  the  potato  crop  may 
be  largely  avoided  through  the  observance  of  certain  precautionary 
measures.  In  the  first  place,  eelworm-infested  tubers  sliould  never 
be  used  for  seed  purposes;  use  only  clean  seed.  Practise  at  least 
a  three-  or  four-year  rotation  on  land  knowai  to  be  infested  with 
eelworm.  Use  rotation  crops  that  are  resistant  to  them,  such  as 
velvet  beans,  beggar  weed,  and  certain  resistant  strains  of  cowpeas.* 
By  such  practice,  the  eelworm  may  be  largely  exterminated  through 
.starvation.  Clean  cultivation  of  these  crops  is  necessary  to  the 
successful  starving  out  of  the  eelworm,  as  the  weeds,  if  permitted 
to  grow,  might  serve  as  host  plants  for  this  pest. 

QUESTIONS  ON  THE  TEXT 

1.  To  what  extent  do  these  pests  injure  the  potato  crop? 

2.  Into  what  two  general  groups  may  these  pests  be  divided? 

^.  Name  the  four  classes  into  which  the  two  groups  are  divided? 

4.  To  what  group  does  the  Colorado  beetle  belong? 

5.  Give   a   brief    history   of   the    eastward    march    of   the    potato    beetle? 

6.  What  is  its  life  history? 

7.  How  is  it  controlled? 

8.  Describe  the  potato  flea  beetle  and  tell  of  its   injury. 
!).  How  can  the  Ilea  beetle  be  controlled? 

10.  Describe  the  three-lined  potato  beetle.     Give  its  life  history. 

11.  What  remedial  measures  are  advocated? 

12.  Describe    the    tortoise    beetles    and   give    distinguishing    characters    of 

three  species. 

13.  Wliat  is  their  life  history?     How  are  they  best  controlled? 

14.  Describe  the  blister  beetles  and  their  injury. 

15.  How  are  they  best  controlled? 

16.  Describe  the   stalk-borer   and    its   work. 

17.  Give  its  life  history  and  control. 

18.  Describe  the  potato  stalk-weevil. 

19.  Give  its  life  history  and  control 

20.  How  do  cutworms  injure  the  potato?     How  many  species  attack  it? 

21.  Give  their  life  history  and  control. 

22.  What  is  the  natural  food  of  the  white  grub? 

*  For  a   larger   list  of   immune   or   resistant   crop   plants   see: — U.    S. 
Dept.  Agr.  Farmers'  Bulletin,  648. 


REFERENCES  CITED  321 

23.  Upon  what  parts  of  the  potato  plant  does  it  feed? 

24.  Give  life  histoiy  and  control. 

25.  Describe  the  wireworms  and  their  work. 

26.  Give  the  life  history  and  control. 

27.  By  whom  and  at  what  date  was  the  potato  tuber  moth  first  mentioned 

in   literature? 

28.  Give  its  origin  and  distribution. 

29.  Describe  the  potato  tuber  moth  and  its  injury. 
;10.  Give  its  life  history  and  control. 

31.  How  would  you  deal  with  insect  infested  tubers  in  storage? 

32.  Give  a  common  name  of  potato  aphids.     What  kind  of  mouth  parts? 

33.  Give  its  life  history  and  control. 

34.  Describe   the   application   of   insecticide   to   the    lower    surface   of   the 

leaves. 

35.  Describe  the  four-lined  leaf-bug  and  its  work. 

36.  What  remedial  measures  are  recommended? 

37.  When   was  the  apple   leafhopper   first   regarded  as   a  potato  pest? 

38.  Describe  it  and   its  work. 

39.  What  is  its  life  history  and  control? 

40.  How  may  one  detect  the  presence  of  the  eelworm  in  the  potato  crop? 

41.  Give  the  life  history  of  the  eelworm. 

42.  What  preventive  measures  can  be  employed? 

QUESTIONS  AND  EXERCISES  SUGGESTED  BY  THE  TEXT 

1.  Name  the  five  leading  insect  or  animal  enemies  of  the  potato  in  order 

of  their  local  importance. 

2.  Collect  specimens  of  such  insects. 

3.  Collect  samples  of  injuries  from  such  enemies. 

4.  What  methods  of  control  are  used  by  local  growers  against  the  worst 

enemies  ? 

5.  Calculate  the  annual   cost  of   such   control   measures  on   one  or   more 

farms. 

6.  Calculate  the  saving  by  same. 

References  Cited 

1.  Ball,   E.   D.    1918.     The   potato   leafhopper   and   the   hopperburn   that 

it  causes.     Wis.  l^tate  Dent.  Agr.  Bid.  20,  Dec.  31,  1918,  p.  76-102, 

pi.  6. 
1919.     The  potato  leafhopper  and  its  relation  to  hopperburn.     Jour. 

Econ.  Ent.  V.  12,  No.  2,  April,  1919,  p.  149-155,  pi.  5,  fig.  1. 
1919.     The  potato  leafhopper  and  the  hopperburn.     In  Phytopath, 

V.  9,  No.  7,  July,  1919,  p.  291-293. 

2.  Berthon,  H.     1855.     On  the  potato  moth.     In  Papers  and  Proc.  Roy. 

Soc.  Tan  Deman's  Land.     Vol.  3,  pt.  1,  p.  76-80. 

3.  Brittaix,  W.  N.     1917.    Two  Important  Vegetable  Pests.    Nova  Scotia 

Coll.  Agr.  Circ.  26:  1. 

4.  Britton,  W.  E.    1918.   Insects  attacking  the  potato  crop  in  Connecticut. 

Conn.  Agr.  Exp.  Sta.  But.  208,  Oct.,  1918,  p.  103-119,  illus. 

5.  Byars,  L.  p.     1919.    Eelworm  disease  of  the  potato.    Potato  Mag.  V.  1, 

No.  12,  June,  1919,  p.  10. 

6.  Chittenden,  F.  H.  1913.     The  potato  tuber  moth.     U.  8.  Dept.  Agr. 

Farmers'  Bui.  557,  Oct.,  1913,  7  p.,  illus. 
21 


322  PARASITES 

1917.     How  to  increase  the  potato  crop  by  spraying.     U.  8.  Dept. 

Agr.  Farmers'  Bui.  868,  Sept.,  1917,  22  p.  illus.' 

7.  Clarke,   Warren   T.      1901.      The   potato-worm   in   California.      Calif. 

Agr.  Exp.  Sta.  Bui.  135,  Oct.,  1901,  30  p.,  illus. 

8.  DoTEN,  S.  B.     1911.     The  potato  eelworm.     Nev.  Agr.  Exp.  Bfa.  Bui. 

76,  March,  1911,  7  p.,  illus. 

9.  EssiG,  E.  O.     1913.     The  potato  tuber  moth.     In  Mo.  Bui.  Calif.  Hort. 

Com.,  V.  2,  No.  9,  p.  665-666,  fig.  365. 

10.  Fayville,  E.  E.  and  Parrott,  P.  J.      1899.     The  potato  stalk-weevil. 

Kan.  Agr.  Exp.  8ta.  Bui.  82,  Jan.,  1899,  12  p.,  illus. 

11.  Gibson,  A.      1909.      Insects   for   the   year    1908   at   Ottawa.      In   SOth 

Ann.  Rpt.  Ont.  Ent.  Soc,  p.  116-120. 

12.  Graf,  J.   E.      1917.     The  potato  tuber   moth.      U.   S.  Dept.  Agr.   Bui. 

427,  Feb.,  1917,  56  p.,  illus. 

13.  HousER,   J.   S.,   GuYTON,   F.   L.,  and  LowRY,  P.   R.      1917.      The  pink 

and  green  aphid  of  the  potato.     Ohio  Agr.  Exp.  Sta.  Bui.  317,  p. 
61-88,  illus. 

14.  Le  Baron,  W.     1853.     Observations  upon  two  species  of  insects  injuri- 

ous to  fruit  trees.     In  Prairie  Farmer,  Sept.,  1853,  p.  330-331. 

15.  Metcalf,  C.  L.     1915.    A  mechanical  measure  for  controlling  Ilea  beetle 

(Epitrix  fuscula).     Jour.  Econ.  Ent.  8:   240-241,  illus.      1915. 

16.  OsBORN,  H.     1896.     A  new  pest  of  potatoes.     Iowa  Agr.  Exp.  8ta.  Bui. 

33,  p.  603-605. 

17.  Patch,  Edith  M.     1907.     The  potato  plant  louse.     Maine.  Agr.  Exp. 

Sta.  Bui.  147,  Nov.,  1907,  p.  235-257,  illus. 

^1919.      Spray   pink   and  green  potato   aphids.     Potato  Mag.   V.    1, 

No.  12,  June,  1919,  p.  8,  illus. 

18.  PoPENOE,   E.   A.      1877.     A  'list   of   Kansas    Coleoptera.      Trans.   Kan. 

Acad.  8ci.   (1876)   6:  39,  1877. 

19.  RuGGLES,  A.  G.,  and  Graham,  S.  A.     1919.     Potato  insects.     In  Minn. 

Farmers'  Inst.  Ann.,  No.  3,  p.  96. 

20.  ScoFiELD,  C.  S.     1912.     The  nematode  gallworm  on  potatoes  and  other 

crop  plants  in  Nevada.     U.  S.  Dept.  Agr.,  Bur.  Pit.  Indus.  Circ.  91, 
Feb.,  1912,  15  p.,  illus. 

21.  Zelleu,  p.  C.     1873.     Beitrage  zur  Kenntnis  der  Nordamericanischer 

Nachf alter,  besonders  der  Microlepidopteren.     Alt.  2,  p.  63. 


CHAPTER  XVII 

FUNGICIDES  AND  INSECTICIDES:  THEIR  PREPARA- 
TION, USE,  APPLICATION,  AND  RESULTANT 
BENEFITS.    SPRAY  EQUIPMENT  AND 
CLASSIFICATION 

General  Discussion. — In  previous  chapters  it  has  been  clearly 
shown  that  maximum  potato  crops  are  dependent,  in  no  small 
measure,  upon  the  degree  of  protection  given  the  plants  against 
the  attack  of  fungous  or  insect  pests  through  fungicidal  or  insecti- 
cidal  applications.  In  the  present  chapter  it  is  proposed  to  give  a 
list  of  the  more  commonly  used  fungicides  and  insecticides  for  the 
control  of  disease  or  insect  enemies  of  the  potato  plant  and  tuber. 
It  has  been  shown,  in  the  chapter  on  diseases,  that  certain  fungous 
pests  attack  both  plant  and  tuber ;  that  others  attack  only  the  foli- 
age, or  only  the  tuber;  that  some  are  controlled  by  spraying  the 
plants,  and  others  by  treating  the  seed.  In  the  case  of  insect  pests, 
it  has  been  noted  that  some  are  controlled  by  poisons;  others  by 
contact  insecticides;  some  by  poisonous  gases;  and  still  others  by 
wdiat  we  call  repellents;  as,  for  example,  the  presence  of  a  good 
coating  of  Bordeaux  mixture  over  the  surface  of  the  leaves  of  a 
potato  plant  serves  as  a  more  or  less  effective  repellent  against  the 
attacks  of  the  flea  beetle  and  the  potato  leafhopper. 

Group  Classification  of  Fungicides  and  Insecticides. — For 
the  sake  of  convenience  in  discussion,  the  fungicides  and  insecticides 
have  been  grouped  according  to  their  uses. 


Fungicides 
controUin  g 


Foliage  diseases 


Tuber  diseases 


Bordeaux  mixture 
Bordeaux  paste 
Dry  Bordeaux 
Pyrox 

Corrosive  sublimate 
Formalin  solution 


323 


324 


FUNGICIDES  AND  INSECTICIDES 


Insecticides 
controlling 


Leaf-fhewinj'  insects 


Sucking  insects 


Paris  green 
Arsenate  of  lead 
Calcium  arsenate 
Arsenoids 
Arsenite  of  zinc 
Pyrox 
Bug-death 

I  Nicotine  sulphate 
•{  Kerosene  emulsion 
Whale-oil  soap 


Tuber-eating  insects    J  c'arbon  bisulphide 


Thus,  Ave  have  fungicides  controlling  foliage  diseases,  and  those 
that  control  certain  diseases  affecting  the  tubers.  In  a  similar 
manner,  there  are  insecticides  that  control  leal'-eating  insects; 
others  that  control  sucking  insects,  etc. 

Fungicides  Controlling  Foliage  Diseases. —  in  the  discussion 
of  the  fungicides  controlling  foliage  diseases,  it  is  proposed  to 
devote  the  major  portion  of  it  to  Bordeaux  mixture,  because  it  is 
believed  to  be  the  most  important  fungicide  yet  available  for  the 
control  of  the  early  and  late  blight. 

Bordeaux  Mixture. — The  history  of  the  origin  of  this  fungicide 
is  ratlier  interesting  in  tliat  it  may  be  regarded  as  of  accidental 
occurrence.  The  discovery  that  milk  of  lime,  to  which  a  cop})er 
salt  had  been  added,  possessed  fungicidal  ]iro])erties  was  tlie  result 
of  an  attempt  on  the  part  of  certain  viiieyardists  in  the  vicinity 
of  Margaux,  St.  Julian,  and  Pauillac,  France,  to  deter  travellers 
in  that  region  from  molesting  the  fruit  in  the  vineyards  bordering 
the  public  highways.  The  salt  of  copper  was  added  to  the  lime 
to  give  it  the  appearance  of  a  poisonous  compound.  It  was  noted 
in  1882,  during  a  severe  epidemic  of  the  downy  mildew  of  the  grape, 
that  the  foliage  of  the  vines  to  which  the  above  mixture  had  been 
applied  remained  green  and  healtby,  while  the  leaves  on  adjacent 
vines  not  sprayed,  or  those  that  liad  received  an  application  of 


PREPARATION  OF  BORDEAUX  MIXTURE  325 

milk  of  lime  alone,  were  destroyed  by  the  mildew.  In  1885 
Millardet,"  as  a  result  of  experimental  studies,  published  an  article 
in  which  he  gave  the  following  directions  for  preparing  the  mix- 
ture, which  was  then  known  under  the  name  of  "bouillie  bordelaise." 
"In  100  litres  of  water  (26.42  gallons)  dissolve  8  kilos  (17.6 
pounds)  of  commercial  sulfate  of  copper.  In  30  litres  of  water 
(7.93  gallons)  slake  15  kilos  (33.1  pounds)  of  quicklime.  Add  the 
milk  of  lime  to  the  copper  sulfate  solution  and  stir  it  well."  This 
mixture,  in  the  absence  of  spray  equipment  such  as  we  now  have, 
was  applied  to  the  foliage  by  means  of  a  small  whisk  broom. 
Such  was  the  origin  of  the  fungicide  now  so  widely  known  as 
Bordeaux  mixture.  The  name  it  now  bears  must  have  soon  re- 
])laced  that  of  "bouillie  bordelaise,"  as  it  was  known  in  this  country 
as  Bordeaux  mixture  in  1889.  The  formula  in  general  use  in 
1889  and  1890  called  for  (>  pounds  of  copper  sulfate  and  4  of 
quicklime  to  22  gallons  of  water.  Bordeaux  mixture  of  this  com- 
position was  made  by  the  writer  and  applied  to  potato  plants  with 
a  watering  can  in  1890.  A  single  application  of  this  mixture,  in 
the  latter  part  of  the  growing  season,  was  sufficient  to  thoroughly 
])rotect  potato  foliage  against  a  severe  epidemic  of  late  blight, 
which  completely  destroyed  unsprayed  plants. 

The  present  standard  Bordeaux  mixture  formula  for  potatoes  is 
known  as  the  5-5-50 ;  that  is,  5  pounds  copper  sulphate,  5  pounds 
lime  and  50  gallons  of  water.  In  regions  where  late  blight  is  of 
infrequent  occurrence,  or  in  seasons  when  the  climatic  conditions 
are  unfavorable  to  its  development,  a  4-4-50  Bordeaux  will  give 
satisfactory  results.  In  fact,  some  pathologists  now  favor  the 
weaker  mixture,  but  it  is  believed  that  material  of  this  strength  will 
not  so  elTectively  control  late  blight  as  will  the  5-5-50  formula. 

Preparation  of  Bordeaux  Mixture. — Although  the  preparation 
of  Bordeaux  mixture  is  comparatively  simple,  it  is  surprising  how 
often  it  is  improperly  made;  this,  too,  in  spite  of  the  fact  that 
practically  every  Experiment  Station  and  farm  paper  in  the  country 
has  published  detailed  instructions  as  to  how  it  should  be  made. 
The  reason  for  this  failure  to  observe  the  prescribed  rules  is,  we 
believe,  due  to  a  lack  of  appreciation  of  the  fact  that  good,  bad  and 
indifferent  Bordeaux  mixture  can  be  manufactured  from  the  same 
ingredients.  A  thorough  understanding  of  what  constitutes  good 
Bordeaux  mixture,  and  Avhat  details  are  necessary  to  observe  in 
order  to  secure  it,  is  the  first  essential  to  success.     A  good  Bordeaux 


326  FUNGICIDES  AND  INSECTICIDES 

mixture  is  oue  in  which  the  precipitate  formed  by  the  copper  salt 
and  the  lime  is  in  a  very  finely  divided  or  flocculent  condition. 
The  question  may  be  asked :  What  has  the  fineness  of  the  precipi- 
tate got  to  do  with  the  quality  of  the  Bordeaux  mixture?  The 
answer  is  that  the  more  finely  divided  the  particles  constituting 
the  precipitate,  the  longer  will  they  remain  in  suspension  in  the 
liquid,  and  the  more  evenly  and  more  completely  will  they  cover 
the  foliage  of  the  potato  plant.  A  bad  Bordeaux  mixture  is  one 
in  which  the  precipitate  is  in  the  form  of  coarse  particles  which 
quickly  settle  to  the  bottom  of  the  spray  tank,  unless  the  material 
is  kept  in  a  constant  state  of  agitation,  and  which  has  a  tendency 
to  clog  the  nozzles  and  to  spread  unevenly  over  the  surface  of 
the  leaves. 

Three  Steps  in  Making  Bordeaux. — The  next  proljlem  con- 
fronting us  is,  how  to  make  good  Bordeaux  mixture.  Practically 
all  directions  that  have  been  published  concerning  the  making  of 
Bordeaux  mixture,  if  adhered  to  closely,  will  insure  a  good  Bordeaux 
mixture.  Let  us  see  what  the  successive  steps  are  in  the  manu- 
facture of  Bordeaux  mixture.  (1)  In  the  first  place,  we  are 
instructed  to  weigh  out  5  pounds  of  copper  sulphate,  if  a  50-gallon 
spray  tank  is  to  be  used,  or  10  pounds  if  a  100-gallon  spray  tank 
is  available.  The  crystalline  copper  sulphate,  or  blue  vitriol  as  it 
is  often  called,  is  to  be  dissolved  in  water,  say  20  gallons,  in  a 
wooden  vessel;  an  earthen  vessel  may  be  used,  but  never  a  metal 
one  as  the  copper  corrodes  the  metal.  The  crystals  may  be  more 
quickly  brought  into  solution  by  using  a  small  volume  of  hot  water, 
or  by  enclosing  them  in  a  coarse  sack  or  piece  of  cheesecloth  and 
suspending  them  in  the  upper  surface  of  the  water.  (2)  Weigh 
out  an  equal  quantity  of  quicklime  or  slightly  more  of  the  hy- 
drated  lime,  and  slake  it  in  a  separate  vessel,  using  just  enough 
water  to  make  a  thick  paste  when  slaked ;  then  add  sufficient  water 
to  make  20  gallons.  (3)  The  copper  sulphate  solution  and  the 
milk  of  lime  should  then  be  simultaneously  poured  together  in  a 
third  vessel,  thoroughly  stirred  and  made  up  to  volume  (Fig.  184), 
in  this  case  to  50  gallons.  The  fineness  of  the  i)recipitate  is  directly 
dependent  upon  diluting  the  two  ingredients,  then  pouring  them 
together  at  about  the  same  rate  into  a  third  vessel  and  thoroughly 
stirring  the  mixture. 

Bad  Bordeaux  mixture  or  one  in  which  the  precipitate  is 
in  the  form  of  coarse  particles,  is  the  direct  result  of  pouring  the 


BAD  BORDEAUX  MIXTURE 


321 


two  ingredients  together  in  a  concentrated  form,  or  by  pouring  the 
one  into  the  otlier  without  proper  dihition.  The  worst  mixture 
seems  to  result  from  pouring  the  undiluted  copper  solution  into 
the  milk  of  lime.  Many  grOM-ers  make  a  practice  of  putting  the 
concentrated  copper  solution  into  the  spray  tank  and  then  adding 
the  milk  of  lime  to  it,  after  which  they  add  the  necessary  water 
to  bring  it  up  to  the  required  volume.  This  is  a  bad  practice  and 
should  be  unequivocally  condemned.     Practically   all  improperly 


Fig.  184.— Bord 
and  then  pouring  the  two  together  as  show 


eaux  mixture  is  made  by  making  the  two  suock  solutions  separately 

n.  (U.    •    -    " 


(U.  S.  Dept.  of  Agriculture.) 


made  Bordeaux  mixture  is  the  result  of  an  attempt  on  the  part  of 
the  grower  to  economize  on  equipment,  as,  for  example,  a  few 
50-gallon  barrels.  It  is  believed  that,  even  from  the  labor-saving 
standpoint,  this  is  a  false  economy;  and  there  certainly  can  be  no 
question  about  the  wisdom  of  such  a  procedure  when  it  results  in  the 
manufacture  of  inferior  mixture.  The  object  of  introducing  the 
above  discussion  is  not  for  the  purpose  of  decrying  labor-saving 
methods,  or  the  desirability  of  eliminating  all  unnecessary  equip- 
ment, but  rather  to  remind  those  who  are  disposed  to  adopt 
shortcuts  that  there  is  such  a  thing  as  a  wasteful  economy,  a  saving 
of  pennies  at  the  expense  of  dollars,  which  results  in  loss  rather 
than  in  gain.     The  operator  should  believe  fully  in  the  adoption 


328 


FUNGICIDES  AND  INSECTICIDE8 


of  all  nietliods  that  make  for  the  elimination  of  waste  effort,  and 
which,  at  the  same  time,  j^roduces  a  high  grade  Bordeaux  mixture. 
System  in  the  Work. — One  of  the  most  efficient  labor-saving 
devices  in  the  manufacture  of  Bordeaux  mixture  is  that  of  the 
spray  mixing  platform,  and  the  stock  solution  barrels.  The  fol- 
lowing description  is  one  which  the  writer  prepared  for  the 
Seventeenth  Annual  Report  of  Hie  Vermont  Agriciilfiinil  Experi- 
ment Station  for  the  years  1903-04,  p.  440-442: 


Fig.  185. — Spray  mixing  platform  at  the  Vermont  Experiment  Station  showins  opera- 
tion of  filling  spray  barrel.  Barrels  in  rear  of  upper  platform  contain  tlie  stock  solutions, 
those  iu  the  front  are  the  dilution  barrels  while  the  one  with  the  strainer  is  the  mixing  barrel. 

"The  horticultural  department  has  devoted  considerable  attention,  dur- 
ing the  past  two  seasons,  to  simplifying  the  labor  of  making  Bordeaux 
mixture.  Two  objects  were  in  view :  ( 1 )  To  avoid  lifting,  so  far  as 
practicable.  (2)  To  promote  the  formation  of  a  fine  precipitate,  and,  there- 
fore, of  a  perfect  mixture. 

"A  Gravity  System. — To  obviate  the  necessity  of  lifting  the  mixture, 
when  lining  the  spray  pump  barrel,  a  lean-to  shed  was  used  to  serve  the 
purpose  of  a  temporary  support  to  a  two-tier  stage  or  platform.  (Fig.  185). 
On  the  upper  platform  were  disposed  the  1)arrels,  which  were  intended  for 
stock  solutions  of  lime  and  copper  sulfate,  and.  also,  those  in  which  these 
solutions  were  to  be  diluted,  preparatory  to  mixing  in  the  third  vessel  on 
the  platform  below.  These  dilution  vessels  were  provided  with  good  sized 
faucets  which  were  brought  sufficiently  close  together  to  allow  the  liciuid, 


S'iSTEiM  IN  THE  WORK 


329 


flowing  from  lioth  at  the  same  time,  to  be  caught  in  a  spout  which  emptied 
into  the  barrel  on  the  lower  level.  The  two  solutions,  simultaneously 
flowing  into  this  spout,  form  Bordeaux  mixture  during  their  flow  along 
the  spout;  the  precipitate,  being  extremely  fine,  passes  through  the 
cheesecloth  strainer  stretched  over  the  top  of  the  barrel.  The  contents 
of  the  mixing  vessels  were,  in  turn,  transferred  to  the  spray  tank  through 
a  pipe,  connected  with  the  lower  part  of  the  barrel  and  extending,  at  right 
angles  to  it,  over  the  spray  tank,  and  being  directed  into  it  by  means  of  a 
short  ell.  The  flow  of  the  Bordeaux  mixture  through  the  pipe  was  con- 
trolled by   means   of  a   brass  valve.     In   this   way,   a   perfect   mixture   is 


Fig.  186. — A  spray  mixing  platform  ami  imh  M  '  nf  n^i  !  li\  flu  \  ^  Dept  of  Agri- 
culture at  Honeoye  Falls,  N.  Y.  The  only  liftiiifi;  iir  (--iij  w  ith  this  outfit  was  that  involved 
in  transferring  the  stock  solutions  to  the  mixing  barrels. 

obtained,  since  the  reaction  takes  place  in  the  short  spout  and  on  the 
strainer,  and  is  continued  in  the  mixing  barrel  and  in  its  transfer  from  it 
to  the  spray  tank,  where  it  passes  through  a  brass  strainer  before  flowing 
into  the  sprayer  {Fig.  185).  Where  flowing  water  is  available,  the 
only  lifting  involved  with  such  a  platform  and  supply  of  barrels  is  that 
of  transferring  the  necessary  volume  of  the  stock  solutions  to  the  dilution 
barrels;  the  remaining  operations  being  all  accomplished  by  gravity,  except 
that  the  water  used  for  diluting  the  stock  solutions,  flows  into  them  under 
pressure.  On  a  mixing  platform,  constructed  at  a  later  date,  the  water 
supply  was  obtained  by  gravity  from  a  storage  tank  mounted  on  an 
upper  bench  of  the  platform.  The  storage  tank,  in  this  case,  was  filled 
from  a  well  beneath  by  a  power  pump   (Fig.  186). 


330  FUNGICIDES  AND  INSECTICIDES 

"Stock  Solutions. — ]Mueh  valuable  time  may  be  saved  by  maintaining 
a  constant  supply  of  stock  solutions  on  hand.  Stock  solutions  are  highly 
concentrated  solutions  of  copper  sulfate  and  lime  kept  in  separate  vessels. 
They  are  usually  made  so  that  each  gallon  of  the  solution  represents  a 
pound  of  the  ingredient  of  which  they  are  composed;  hence,  if  one  wishes  to 
make  up  50  gallons  of  Bordeaux  mixture,  he  takes  5  gallons  from  each 
stock  vessel  and  pours  them  into  the  dilution  barrels — this  will  represent 
the  amounts  called  for  in  the  5-5-50  formula.  Stock  solutions  may  be 
made  that  represent  2  pounds  of  copper  sulfate  or  lime  per  gallon,  or  in 
the  case  of  the  copper  sulfate,  one  may  make  what  is  known  as  a  saturated 
solution,  that  is,  one  to  which  an  excess  of  the  copper  salt  has  been  added. 
A  gallon  of  such  a  solution  is  said  to  contain  somewhat  less  than  three 
pounds  of  the  copper  salt.  Owing  to  the  fact  that  a  gallon  of  the  saturated 
solution  represents  two  and  a  fractional  part  of  a  pound,  and  therefore 
is  less  easily  measured  out,  it  is  not  recommended.  A  saturated  stock 
solution  has  one  advantage  over  an  unsaturated  one  in  that  it  is  not 
necessary  to  account  for  the  moisture  lost  through  evaporation,  as  is  the 
case  with  the  latter.  Losses  occurring  in  the  less  concentrated  stock  so- 
lutions may  be  rectified  by  marking  the  height  of  the  solution  in  the  barrel 
when  through  spraying,  and  bringing  it  up  to  this  mark  when  spraying  is 
resumed.  Stock  solutions  may  be  kept  almost  indefinitely,  Init  it  is  never 
advisable  to  hold  over  unused  Bordeaux  mixture;  it  should  always  be 
freshly  prepared.  Another  precaution  to  be  observed  is  to  always  thor- 
oughly stir  up  the  stock  solutions  before  measuring  out  the  quantities 
required  in  making  a  fresh  lot  of  Bordeaux  mixture.  This  precaution  is 
especially  pertinent  in  the  case  of  the  lime,  as  severe  burning  of  the  foliage 
is  certain  to  result  if  only  the  clear  lime-water  liquid  is  taken  to  make 
Bordeaux  mixture." 

Application  of  Bordeaux  Mixture. — Maximum  results  from 
proper!}'  made  Bordeaux  mixture  can  only  be  obtained  under  the 
following  conditions : 

1.  Its  application  at  the  proper  time. 

2.  Its  application  under  sufficient  pressure  and  through  properly 
constructed  spray  nozzles,  so  as  to  give  a  fine,  even  distribution  of 
the  spray  material. 

3.  Applications  sufficiently  often  to  keep  tlie  new  foliage  thor- 
oughly covered. 

4.  Use  poison  with  the  mixture  when  it  is  desired  as  an  insecti- 
cide as  well  as  a  fungicide. 

It  is  difficult  to  lay  down  any  fixed  rules  as  to  the  proper  time 
to  spray  except  in  a  rather  general  way.  In  localities  where  late 
blight  is  common  and  usually  prevalent,  it  is  a  good  practice  to 
begin  spraying  as  soon  as  the  plants  are  from  8  to  10  inches  high. 
This  is  usually  sufficiently  early  to  arrest  the  development  of  early 
blight  and  to  afford  some  measure  of  protection  against  flea  beetle 
injury  by  serving  as  a  repellent.  Subsequent  spraying  should  be 
frequent  enough  to  keep  the  new  growtli  well  covered  with  the 


PYROX  331 

fungicide.  Wlien  the  weather  is  dry  and  hot,  the  sprayings  may 
be  less  frequently  made  than  when  the  opposite  conditions  prevail. 

Bordeaux  Paste. — Bordeaux  paste  is  a  commercial  Bordeaux 
mixture  product  from  which  the  excess  moisture  has  been  removed ; 
it  is  offered  to  the  trade  in  various  sized  packages  np  to  a  large  sized 
keg.  All  that  is  necessary  to  convert  it  into  a  Bordeaux  mixture 
is  to  add  the  required  amount  of  water.  It  is  not  as  efficient  in  the 
prevention  of  late  blight  as  is  fresh,  home-made  Bordeaux  mixture 
when  properly  made.  This  is  largely  due  to  the  fact  that  the 
Bordeaux  paste  forms  a  coarser  precipitate,  and  consequently  gives 
much  the  same  result  as  the  poorly  made  Bordeaux  mixtures  previ- 
ously described. 

Dry  Bordeaux  contains  the  copper  sulfate  and  lime  in  a  dry, 
povvdered  form,  and  is  intended  to  be  applied  as  a  dust.  Bird- 
recommends  the  following  method  of  preparing  dry  or  powdered 
Bordeaux.  Dissolve  10  pounds  of  copper  sulfate  in  4  gallons 
of  hot  water.  Slake  5  pounds  of  quicklime  in  4  gallons  of  water. 
Slake  remaining  lime  (full  barrel  minus  the  5  pounds)  to  a  per- 
fectly dry  dust.  Pour  the  copper  and  the  milk  of  lime  solutions 
together,  simnltaneoushr,  into  a  third  vessel,  and  stir  until  no 
greenish  streaks  appear;  then  distribute  the  mixture  over  the  lime 
dust  and  mix  with  a  rake.  While  still  somewhat  damp,  rub  it 
through  a  sieve  and  spread  out  to  dry.  This  requires  a  day  or 
two,  after  which  the  mixture  will  keep  indefinitely.  These  quan- 
tities make  aljout  200  ])ounds  of  powder. 

Commercially  prepared  Bordeaux  powder  is  a  regular  article 
of  commerce,  but  as  yet  it  has  not  come  into  much  favor  in 
potato  spraying.  This  statement  should  not,  however,  be  taken 
as  a  final  verdict  in  regard  to  the  use  of  Bordeaux  powder  as  a 
fungicide  for  the  potato  crop.  The  constant  improvement  that  is 
being  made  in  dust  spray  equipment  has  made  these  fungicides 
much  more  effective  in  the  control  of  plant  diseases.  Dust  sprays 
adhere  best  when  applied  in  the  early  morning  or  late  evening, 
when  the  foliage  is  moist  with  dew. 

Pyrox  is  a  proprietary  compound  possessing  both  fungicidal 
and  insecticidal  properties.  It  is  a  more  expensive  fungicide  than 
Bordeaux  mixture,  and  does  not  give  quite  as  good  results  as  the 
fresh,  properly  prepared,  home-made  Bordeaux.  The  heavier  initial 
cost  of  Pyrox  is,  to  some  extent,  offset  by  the  fact  that  it  is 
immediately  availal)le  for  use  upon  the  addition  of  the  required 


332  FUNGICIDES  AND  INSECTICIDES 

volume  of  water,  and,  in  addition,  contains  sufficient  poison  to  serve 
as  an  insecticide.  Use  at  the  rate  of  10  pounds  to  50  gallons 
of  water. 

Bug-Death. — The  manufacturers  of  bug-death  claim  that  it  is 
an  effective  fungicidal  and  insecticidal  compound :  but  wherever 
it  has  been  carefully  tested  it  has  not  fully  protected  the  foliage 
from  late  blight,  in  fact  it  only  gave  slight  protection.  When  used 
liberally,  it  does  control  leaf-eating  insects.  It  is  too  expensive 
to  use  as  an  insecticide,  at  least  in  commercial  fields. 

Fungicides  Controlling  Tuber  Diseases. — It  is  realized  that 
this  caption  is  rather  misleading  since  there  are  tuber  diseases 
that  cannot  be  controlled  by  fungicides.  It  is  hoped,  however, 
that  its  use  in  this  connection  may  be  justified  on  the  basis  of 
conformity  to  the  other  terms  employed ;  as,  for  example,  fungicides 
are  employed  as  disinfectants,  their  function  being  to  destroy 
the  fungous  organisms  causing  common  scab,  and  the  black  scurf 
or  rhizoctonia;  also  to  destroy  other  spores,  particularly  those  of 
blackleg,  which  may  be  lodged  on  the  outer  surface  of  the  tuber. 
The  function  of  these  fungicides  ceases  with  the  destruction  of  such 
organisms  as  have  been  mentioned,  which  occur  on  the  seed  tuber 
itself.  If  the  disinfected  tubers  are  planted  in  soil  free  from  the 
organisms  of  common  scab  or  of  rhizoctonia,  the  resultant  crop  of 
tubers  should  be  free  from  these  two  diseases;  but  if  the  soil  is 
infected,  the  new  tubers  are  also  likely  to  be  infected.  Treatment 
of  the  seed  tubers,  therefore,  simply  destroys  the  organisms  of  these 
diseases  upon  the  surface  of  the  tuber.  It  is  a  guarantee  of  a 
clean  crop  only  when  the  land  in  which  they  are  grown  is  free 
from  infection. 

Corrosive  Sublimate  Treatment. — Corrosive  sublimate  was 
the  first  fungicide  to  be  successfully  emi)loyed  in  the  disinfection 
of  seed  potatoes  of  the  disease  known  as  the  common  scab.  It  was 
first  successfully  employed  by  Dr.  H.  Ij.  Bolley,  of  the  North 
Dakota  Experiment  Station,  when  connected  with  the  Indiana 
Experiment  Station  in  the  late  eighties. 

The  formula  recommended  for  potato  seal)  and  rhizoctonia 
disinfection  is  as  follows :  Dissolve  4  ounces  of  corrosive  sublimate 
(Mercuric  chloride,  Hg  CL)  in  a  small  quantity  of  hot  water  in  an 
earthen,  porcelain  or  wooden  vessel  and  dilute  to  30  gallons  of 
water.  Hot  water  is  suggested  as  a  solvent,  because  mercuric 
chloride  dissolves  very  slowly  in  cold  water.  In  many  instances 
the  indifferent  results  that  have  been  secured  from  corrosive  subli- 


FORMALIN  TREATMENT  333 

mate  treatment  have  been  due  to  the  fact  that  the  crystals  or 
powder  have  not  gone  into  solution,  hence  it  was  too  weak  to  be 
effective.  Be  sure  that  the  material  all  goes  into  solution.  The 
quickest  way  to  dissolve  it  is  to  place  the  porcelain  vessel  containing 
the  crystals  and  the  water  over  a  free  tlame  or  on  a  hot  stove, 
and  let  it  come  to  a  boil. 

In  the  use  of  corrosive  sublimate  it  should  be  remembered  that 
the  substance  is  a  deadly  poison.  Every  vessel,  therefore,  with 
which  the  solution  has  come  in  contact  should  be  thoroughly 
cleansed  before  using  it  for  other  pur])oses,  and  every  precaution 
should  be  taken  to  ])revent  accidents  througli  the  drinking  of  the 
solution  by  farm  animals.  All  discarded  material  should  be  so 
disposed  of  as  to  quickly  disappear  in  the  ground.  An  ounce  of 
prevention  is  better  than  a  pound  of  cure. 

The  period  of  treatment  of  the  seed  tubers  in  the  corrosive 
sublimate  solution  varies  with  the  condition  of  the  seed.  If  the 
seed  stock  is  free  from  the  sclerotia  or  resting  bodies  of  rhizoctonia 
and  comparatively  free  from  common  scab,  an  immersion  of 
one-half  hour  will  be  sufficient.  If  the  tubers  are  badly  germinated, 
the  period  of  treatment  should  be  cut  down  to  a  half  hour  to  avoid 
serious  injury  to  the  new  sprouts.  Where  there  is  considerable 
rhizoctonia  infection  and  the  tubers  are  dormant,  a  treatment  of 
one  and  one-half  to  two  hours  is  advisable.  As  soon  as  the  tubers 
are  treated  they  should  at  once  be  spread  out  to  -dry.  It  is  always 
advisable  to  treat  seed  stock  before  cutting  it. 

Recent  investigations  have  shown  that  the  strength  of  corrosive 
sublimate  rapidly  decreases  with  each  lot  of  treated  seed.  It  is 
now  suggested  that  not  more  than  three  lots  be  treated  in  the  same 
solution  witliout  reinforcing  or  renewing  it  (Figs.  187  and  188). 

Formalin  Treatment. — Formalin  is  a  trade  name  applied  to 
a  40  per  cent  solution  of  formaldehyde  gas.  It  is  a  non-poisonous, 
colorless  liquid,  much  more  easily  Imndled  than  corrosive  sublimate 
and  practically  as  effective  in  combating  scab ;  but  it  does  not  seem 
to  have  the  same  penetrative  power  as  corrosive  sul)limate  when  it 
comes  to  destroying  the  resting  felt-like  bodies  (sclerotia) 
of  rhizoctonia. 

It  was  first  employed  as  a  remedy  for  potato  scab  by  Dr.  J.  C. 
Arthur,  botanist  of  the  Indiana  Experiment  Station.  The  actual 
experimental  studies  determining  the  best  strength  of  solution  to 
use,  and  the  most  satisfactory  period  of  treatment  were  worked 


334  FUNGICIDES  AND  INSECTICIDES 

out  by  the  writer,  under  the  direction  of  Dr.  Arthur,  during  the 
winter  of  1895-96.^  Badly  scabbed  tubers  were  treated  in  formalin 
solutions  of  1  to  200,  1  to  400,  and  1  to  800  strengths  and  the 
tubers  grown  in  sterilized  soil  in  a  small  greenhouse  connected  with 
the  botanical  laboratory.  The  1  to  200  strength  was  the  only 
one  that  gave  clean  progeny.  The  formula  now  used,  1  pint  to  30 
gallons  of  water,  is  approximately  1  to  240. 

Period  of  Treatment. — The  period  of  treatment  usually  recom- 
mended is  one  and  one-half  to  two  hours;  but  recent  studies  have 
demonstrated  that  a  much  shorter  period,  one-half  to  one  hour,  is 


Fig.  187. — Treating  seed  potatoes  with  corrosive  sublimate  solution.  The  use  of  the 
slat  crate  as  a  receptacle  is  a  time  saving  proposition  because  the  potatoes  will  dry  off  in  the 
crates  after  their  removal  from  the  solution.  It  also  prevents  re-infection  through  their 
coming  in  contact  with  an  unclean  package.    Courtesy  of  Daniel  Dean,  Nichols,  N.  Y. 

satisfactor}^  The  shorter  period  should  be  used  when  the  tubers 
to  be  treated  are  germinated.  When  they  are  dormant  and  have 
much  scab  or  rhizoctonia  infection,  immerse  the  seed  from  one 
and  one-half  to  two  hours.  After  treating  the  tubers  spread  them 
out  to  dry. 

Insecticides  Controlling  Leaf-chewing  Potato  Pests. — It  is 
well  known  to  every  potato  grower  tliat  the  leaf-chewing  insects 
are  more  easily  controlled  by  insecticides  than  the  sucking  insects. 
This  is  due  to  the  fact  that  they  are  readily  destroyed  by  the 
application  of  poisonous  substances  to  the  foliage.  Arsenical  poi- 
sons are  chiefly  employed  in  the  control  of  leaf-chewing  insects.  The 
poisons  most  commonly  employed  are  Paris  green,  arsenate  of  lead, 
arsenoids,  calcium  arsenate,  arsenite  of  zinc,  pyrox  and  bug-death. 

Paris  Green. — The  insecticide  so  widely  known  under  the  name 
of  Paris  green  is  a  precipitate  of  white  arsenic  and  acetate  of 


PARIS  GREEN 


335 


copper  {verdigris) .  It  may  be  prepared  by  making  a  boiling  bot 
solution  of  each  of  these  two  substances  in  separate  vessels,  and 
then  pouring  them  together,  whereupon  the  substance  we  know  as 
Paris  green  is  precipitated  in  the  form  of  a  very  fine,  clear,  green 
powder.  Its  value  as  an  insecticide  is  due  to  its  arsenical  content. 
Nearly  all  of  the  arsenic  it  contains  is  insoluble  in  water.  Paris 
green  may  be  applied  as  a  liquid  or  a  dust  spray  (Fig.  189).  When 
applied  as  a  liquid  spray,  it  should  be  used  in  connection  with 


Fig.  188. — Treating  seed  potatoes  on  a  large  scale  in  a  corrosive  sublimate  solution. 
Tank  filled  with  165-pound  sacks  of  potatoes.  In  this  case  heavy  lifting  is  avoided  by  use 
of  pulley  blocks.  Platform  at  rear  of  tank  is  used  as  a  draining  board  when  sacks  are  removed. 
Caribou,  Me.,  1914. 

milk  of  lime  equal  to  2  pounds  of  lime  to  50  gallons  of  water, 
or  in  Bordeaux  mixture  to  guard  against  injury  to  the  foliage  from 
the  slight  amount  of  free  arsenious  acid  that  may  be  present.  It 
should  be  used  at  the  rate  of  8  ounces  to  50  gallons  of  water. 
If  the  insects  are  abundant  and  the  poison  can  be  added  to  Bordeaux 
mixture,  it  may  be  used  at  the  rate  of  a  pound  to  50  gallons,  without 
risk  of  injury  to  the  foliage. 

The  dry  poicder  is  most  conveniently  brought  into  suspen- 
sion in  water  by  first  making  a  paste  of  the  Paris  green.  This  is 
very  quickly  accomplished  by  placing  it  in  a  small  vessel,  and 
adding  just  enough  water  to  thoroughly  moisten  the  whole  mass. 
Through  constant  stirring  it  is  soon  brought  into  the  condition 


336  FUNGICIDES  AND  INSECTICIDES 

of  a  paste,  in  which  state  it  readily  mixes  with  water.  When  used 
as  a  dust  spray,  it  should  be  mixed  with  some  neutral  substance, 
such  as  air-slaked  lime,  land  plaster  or  any  other  jjowdered  material 
which  will  act  as  a  carrier  of  the  poison.  There  is  no  generally 
accepted  formula  concerning  the  rate  of  dilution  of  the  dry  form; 
in  fact,  the  recommended  rates  vary  from  1  pound  of  Paris  green 
in    19   pounds   of   the   diluent  to    1    pound  in    99    pounds — with 


Fig.  189  — Applying  a  du«t  spray  of  Pari^    'i      i    i     '    i    -  ' 
potato  plants  to  protei't  iIkmii  as^ainst  the  ravage-,  n    i  i     (  i  I     p  ,i  ii  )  I"    t  1,1 

beetle,  either  or  both  of  which  nuiy  c  luie  serious  injiirv  to  tht  iil  uit-,  ju-,t  .Utci  tin  \  ai)i)i:ir 
above  ground. 

all  the  intermediate  strengths.  Very  good  results  have  been  ol)- 
tained  when  diluted  to  1  in  30  parts.  Occasionally,  growers  are 
found  who  apply  dry  Paris  green  without  diluting  it.  In  such 
cases,  it  is  applied  with  hand  atomizers  which  deliver  a  very  fine 
dust.  It  has  been  used  in  this  way  at  the  rate  of  from  5  to  6 
pounds  per  acre  with  but  slight  injury  to  the  foliage.  Such  prac- 
tice is  both  wasteful  of  the  insecticide  and  dangerous  to  the  health 
of  the  plant,  and  should  never  be  recommended.  Diluted  Avith 
lime  or  other  carrier  and  a])plied  with  a  dust  spray  gun,  when  the 
foliage  is  moistened  with  dew  in  the  early  morning  or  late  even- 
ing, it  adheres  well  to  the  foliage,  and  is  effective  in  destroying 
the  leaf-cliewing  insects. 


CALCIUM  ARSENATE  337 

Arsenate  of  lead  is  a  precipitate  formed  by  the  admixture 
of  solutioijs  of  arseuate  of  soda  and  acetate  of  lead.  Forbush  and 
FernakP  published  the  following  statement  concerning  arsenate 
of  lead : 

"Although  nearly  all  poisons  known  to  lis  which  can  be  used  as 
insecticides  have  been  experimented  with  during  the  past  five  years,  in 
the  hope  that  something  would  be  found  which  would  prove  fatal  to  the 
gypsy  moth,  only  one  which  is  more  ell'ective  than  Paris  green  has  been 
di^covered.  This  is  arsenate  of  lead,  a  poison  slower  in  its  action  than  the 
other,  but  Avhich  has  tliree  distinct  advantages:  ( 1 )  It  can  be  used  at  any 
desired  strength  without  serious  injury  to  the  foliage.  (?.)  It  is  visible 
wherever  used,  as  it  forms  a  whitisli  coating  on  the  leaves.  (3)  It  has 
adhesive  qualities,  given  it  probal)ly  by  the  acetate  of  lead,  and  therefore 
remains  on  the  leaves  for  a  much  longer  period  than  Paris  green." 

The  formula  used  by  the  commission  in  making  tlieir  arsenate 
of  lead  consisted  of  30  parts  of  arsenate  of  soda  and  70  parts 
of  acetate  of  lead.  Fernald  further  suggests  that  it  may  be  pre- 
])ared  in  the  proportion  of  11  ounces  of  acetate  of  lead  to  4  ounces 
of  arsenate  of  soda.  Both  substances  are  brought  into  solution  in 
separate  vessels,  and  then  poured  slowly  together  into  a  third,  the 
precipitate  thus  formed  being  the  arsenate  of  lead. 

Arsenate  of  lead  is  now  commonly  offered  to  the  trade  in  the 
paste  and  in  the  dry  or  powder  form.  The  paste  is  a  little  more 
convenient  to  use,  as  it  is  readily  diluted  with  water  to  the  desired 
strength.  Its  selling  price  per  pound  is  less  than  the  dry  form, 
but  a  much  greater  amount  must  be  used  in  order  to  secure  the 
same  effectiveness,  which  makes  it,  in  reality,  somewhat  more 
expensive  than  the  powder  form. 

In  order  to  be  effective  against  potato  insects,  arsenate  of  lead 
paste  must  he  used  at  the  rate  of  3  to  5  pounds  in  50  gallons  of 
water.     In  the  dry  form,  2  to  3  pounds  is  sufficient. 

The  difficulty  of  mixing  the  dry  arsenate  of  lead  with  water 
may  be  overcome  by  wetting  the  mass.  Then  stir  into  a  thick  paste 
before  diluting. 

Calcium  Arsenate. — This  relatively  new  arsenical  insecticide 
is  being  used  as  a  substitute  for  arsenate  of  lead  or  Paris  green 
to  control  the  potato  beetle.  The  manufacturers  claim  that  it 
contains  more  arsenic  than  the  arsenate  of  lead  powder,  and  that, 
in  consequence,  three-quarters  of  a  pound  of  it  is  equal  to  one  pound 
of  the  arsenate  of  lead  powder.  When  used  alone  as  a  liquid  spray, 
it  is  recommended  that  an  equal  amount  of  hydrated  lime  be  used 
22 


338  FUNGICIDES  AND  INSECTICIDES 

with  it.     Use  at  rate  of  one  and  one-half  to  two  and  one-half 
pounds  to  50  gallons  of  water  or  Bordeaux  mixture. 

Arsenoids. — In  some  sections  of  the  country  and  particularly 
in  Aroostook  County,  Maine,  arsenoids  have  been  used  very  exten- 
sively in  combating  the  potato  beetle.  There  have  been  offered 
to  the  trade,  at  various  times,  preparations  known  as  white  arsenoid, 
pink  arsenoid,  green  arsenoid,  etc.  Morse''  describes  these  arsen- 
oids as  follows : 

"  White  arsenoid  was  supposed  to  be  barium  arsenite,  but  all  of  its 
arsenious  acid  was  free,  so  that  it  was  no  better  than  white  arsenic 
diluted  with  barj'ta.  Pink  arsenoid  is  arsenite  (not  arsenate)  of  lead. 
The  green  arsenoid  or  arsenite  of  copper,  if  pure,  would  carry  about  53 
per  cent  of  combined  arsenious  oxide." 

Other  arsenoids  under  numbers  2,  3,  4  and  5  are  discussed, 
and  the  author  summarizes  the  results  of  his  experiments  with 
these  insecticides  in  the  following  statements : 

"  There  was  not  much  difference  to  be  seen  in  the  way  the  different 
arsenoids  acted.  None  of  them,  at  the  rate  used,  burned  the  foliage;  and 
they  all  killed  the  insects  practically  as  well  as  Paris  green.  The  arsenoids 
are  more  bulky,  and  on  this  account  are  more  readily  kept  in  suspension 
than  Paris  green.  The  field  notes  show  the  arsenoids  to  have  been  about  as 
effective  as  Paris  green,  but  not  so  effective  as  arsenate  of  lead." 

Arsenite  of  zinc  is  a  compound  of  zinc  and  arsenic,  and  is 
not  so  well  kno^vai  as  the  arsenate  of  lead,  as  it  is  a  nev>'er  compound. 
It  is  one  of  the  most  effective  insecticides.  It  is  a  whitish  precipi- 
tate or  powder  that  readily  mixes  with  Avater.  The  adhesive 
properties  of  arsenite  of  zinc  are  as  good,  if  not  better,  than  that 
of  the  arsenate  of  lead.  Used  at  the  rate  of  2  pounds  to  100 
gallons  of  water  it  has  proven  as  effective  as  much  larger  amounts 
of  arsenate  of  lead,  but  it  is  somewhat  more  expensive  per  pound. 
It  is  readily  mixed  with  water,  stays  in  susjiension  well,  and  never 
causes  any  burning  of  the  foliage. 

Pyrox. — As  previously  noted  under  fungicides,  pyrox  is  a  com- 
bination fungicidal  and  insecticidal  preparation,  and  should  never 
be  used  except  when  intended  to  control  fungous  diseases  as  well 
as  insect  pests. 

Insecticides  Controlling  Sucking  Insects. — Sucking  insects 
are  provided  with  a  strong  beak  or  proboscis  which  they  insert 
into  the  tissues  of  the  plant  and  remove  its  Juices.  It  is  evident, 
therefore,  from  the  manner  in  which  they  secure  their  food  supply. 


KEROSENE  EMULSION 


339 


that  arsenical  poisons  are  not  effective  against  this  class  of  insect 
enemies  of  the  potato.  In  order  to  successfully  combat  sucking 
insects,  it  is  necessary  to  employ  what  are  commonly  known  as 
contact  insecticides,  that  is,  insecticides  that  will  kill  by  direct 
contact  through  corrosive  action,  or  through  a  volatile  oil.  Vola- 
tile oil  compounds  are  not  ordinarily  employed  in  spraying  pota- 
toes, hence  they  are  not  considered  in  the  present  discussion.  The 
commonly  employed  insecticides 
are  nicotine  sulfate  or  black- 
leaf  40,  kerosene  emulsion,  and 
whale-oil  soap. 

Black-leaf  40  is  a  proprie- 
tary compound  of  nicotine  sul- 
fate, a  powerful  narcotic 
jjoison.  In  color  and  general 
physical  properties  it  very  much 
resembles  a  low  grade,  black- 
strap molasses.  It  may  be  used 
at  the  rate  of  1  pint  to  50  gallons 
of  water.  On  account  of  the 
ease  with  which  black-leaf  40 
can  be  prepared  for  use,  it  has 
become  a  very  popular  insecti- 
cide   for    the    control    of    the 

potato     aphid     and     other     suck-  Fig.    IOO.-A   type  of  sprayer    called 

ino*   insects  atomizer.     (School  and  Home  Gardening.) 

Kerosene  Emulsion. — Although  kerosene  emulsion  is  one  of 
the  oldest  of  our  home-made  contact  insecticides,  it  is  not  very 
generally  employed.  This,  I  believe,  is  due  to  the  difficulty  that 
most  people  encounter  in  the  preparation  of  an  emulsion  from 
which  the  oil  does  not  separate.  Various  formulas  have  been 
suggested  from  time  to  time  for  its  preparation.  In  general, 
these  formulas  differ  only  in  the  quantity  of  soap  to  use.  For 
example,  "Cook's  hard  soap  emulsion"  calls  for  one-quarter  of  a 
pound  of  hard  soap  such  as  Ivory,  Babbitt,  etc.,  dissolved 
m  two  quarts  of  boiling  water,  to  which  is  added  one  pint  of 
kerosene  oil.  The  oil  and  soap  solution  is  emulsified  by  pumping 
it  back  and  forth  with  a  hand  pump  while  it  is  hot,  until  a 
perfect  emulsion  is  obtained.  This  emulsion  is  diluted  with  twice 
its  volume  before  using. 


340  FUNGICIDES  AND  INSECTICIDES 

The  Ilubbard-liiloy  Kerosene  Emulsion  calls  i'or  the  follow- 
ing amounts : 

Hard  soap    Va  pound 

Kerosene 2     gallons 

Boiling  soft  water 1     gallon 

This  formula  is  prepared  in  the  same  way  as  the  Cook  formula. 
In  the  matter  of  dilution,  however,  tlio  recommendations  are 
different;  this  stock  solution  should  be  diluted  witli  from  4  to 
20  parts  of  water.  The  latter  dilution  should  be  used  in  spra^dng 
potato  plants. 


Fin.  191.— A  bucket 
sprayer  for  very  small  patch- 
es    (Fightsof  the  Farmer.) 


]n2. — Knapsack  Sprayer,  carried 
r)f    the    operator.     (Fights    of   the 


Britton^  recommends  a  still  different  formula  wliuli  \\v  claims 
gave  better  results  than  those  ordinarily  used.  This  formula  calls 
for  somewhat  larger  amounts  of  soap  and  kerosene : 

Laundry  soap   (about  ;10  oiuices) 3  cakes 

Kerosene 4  gallons 

Water 2  gallons 

Emulsify  as  ])reviously  direcled  and  dilute  eiglit  times,  prac- 
tically a  50-gallon  barrel.  Britton  says:  "All  the  ai)hi(ls  liit  by 
the  spray  were  killed  without  injury  to  the  ])lants." 

Whale-oil  Soap. — The  value  of  whale-oil  soap  as  an  insecticide 
for  sucking  insects  has  long  been  recognized.  Tt  is  effective 
against  plant  lice  when  used  at  tlic  rate  of  one  pound  to  10 
gallons  of  water.  The  soap  should  be  shaved  into  tbin  slices, 
dissolved  in  a  small  volume  of  l)oiling  liot  water,  and  iben  diluted 


CONTROLLING  TUBER-EATING  INSECTS 


341 


to  the  required  strength.     Whale-oil   soap   may  also   be   used    in 
place  of  hard  soaps  in  making  kerosene  emulsion. 

Suggestions  for  Spraying  Aphids. — The  value  of  any  of  the 
above  spray  materials  in  the  control  of  sucking  insects  is  directly 
de])endent  upon  the  thoroughness  with  which  it  is  applied.  This 
statement  is  particularly  true  with  the  potato  aphid  which,  as  a 
rule,  feeds  upon  the  under  surface  of  the  leaf,  oftentimes  causing 
it  to  roll  downward  and  inward.  The  spray  material  must  be  so 
directed  as  to  reach  and  cover  the  under 
surfaces  of  the  leaves.  This  can  be  most 
conveniently  accomplished,  when  the 
plants  are  large,  by  suspending  a  rod  or 
other  device  beneath  but  slightly  in  ad- 
vance of  the  spray  nozzles,  and  sufficiently 
low  to  drag  the  tops  over;  this  exposes 
the  lower  surface  of  the  leaves  to  the 
spray  material,  provided  the  nozzles  are 
])roperly  adjusted.  Injury  to  the  vines, 
from  being  dragged  over  in  tliis  manner, 
may  be  minimized  by  slipping  a  slightly 
larger  pipe  over  the  suspended  rod,  so  as 
to  permit  a  revolving  motion  as  tlie  plants 
are  bent  over. 

Insecticides  Controlling  Tuber-eat- 
ing Insects. — The  only  insect  pest  of  the 
tuber  that  can  be  destro3^ed  by  a  gaseous 
compound  is  the  potato  tuber  moth. 
Treatment  can  only  be  applied  when  the 
crop  is  in  storage,  and  the  storage  house  or  room  is  sufficiently  tight 
to  hold  gas  for  a  reasonably  long  period.  The  substance  used  is 
a  colorless  liquid  known  as  carbon  bisulfide.  Graf  recommends 
the  following  dosage:  two  pounds  of  carbon  bisulfide  to  each 
1,000  cubic  feet  of  air  space;  expose  to  fumes  for  48  hours. 
Graf  says  that  at  this  strength  the  larvs  and  adults  and  practically 
all  the  pupse  and  eggs  are  killed.  If  the  tubers  are  noticeably 
infested,  the  fumigation  sliould  be  repeated  in  a  week,  if  in 
summer,  or  in  two  Aveeks  in  winter.  It  is  suggested  that  the 
liquid  should  be  placed  in  shallow  tin  pans  above  the  material 
to  be  treated,  as  the  gas  is  heavier  than  air.  Carbon  bisulfide  gas 
is  a  highly  explosive  compound  when  mixed  with  air,  therefore, 


Fig.  193. — Compressed 
air  sprayer.  This  type  of 
sprayer  fills  about  the  same 
need  as  the  knapsack  type. 


342 


FUNGICIDES  AND  INSECTICIDES 


care  should  be  exercised  not  to  have  it  come  in  contact  with  a  flame 
or  spark. 

Resultant  Benefits  from  Fungicides  and  Insecticides. — The 
resultant  benefits  from  the  use  of  fungicides  or  insecticides  have, 
so  far  as  we  are  aware,  only  been  determined  in  the  case  of  the 
late  blight.  It  is  obvious,  of  course,  that  equally  striking  data 
might  be  collated  with  reference  to  the  injury  caused  by  insects, 
and  particularly  so  by  the  potato  beetle.     In  fact,  it  is  conceivable 


Fig.    194. — Barrel  spray  pump  mounted    on  hand  cart.     Fairly  efficient  sprayer  for 
relatively  small  commercial  areas. 

that  the  crop  might  be  entirely  destroyed,  so  far  as  the  production 
of  marketable  tubers  are  concerned,  if  not  protected  from  the 
ravages  of  insect  pests  by  some  arsenical  application. 

The  most  interesting  data  upon  this  subject  are  those  published 
by  Lutman^  in  which  the  author  discusses  the  results  of  20 
years  of  spraying  with  Bordeaux  mixture,  applied  to  late  matur- 
ing varieties  of  potatoes,  for  the  control  of  late  blight,  by  his  pre- 
decessors in  the  work.  These  results,  as  summarized  on  page  247, 
represent  gains  from  the  use  of  Bordeaux  mixture,  ranging  from 
32  bushels  per  acre  in  1906,  to  224  bushels  per  acre  in  1893. 
The  total  average  yield  per  acre  from  the  sprayed  plants  for  the 
20  years  was  268  bushels  per  acre,  and  163  from  the  unsprayed 
plants,  a  gain  of  105  bushels  per  acre  or  64  per  cent. 


SPRAY  EQUIPMENT 


343 


At  the  New  York  State  Experiment  Station  in  a  ten-year 
spraying  test,  1902  to  1911  inclusive,  at  Geneva,  and  Eiverhead, 
L.  I.,  the  following  average  increases  from  3  and  5  to  7  sprayings 
were  obtained :  Geneva,  N.  Y.,  3  sprayings  resulted  in  an  increase 
over  unsprayed  plants  of  69  bushels  per  acre;  5  to  7  sprayings  97.5 
bushels;  Eiverhead,  3  sprayings  25  bushels,  5  to  7  sprayings 
45.7  bushels. 

Many  other  instances  might  be  cited  where  much  larger  gains 
from  spraying  were  obtained.     One  of  the  most  striking  examples 


Fig.  195. — The  sprayer  in  operation.  When  the  phmts  are  full  grown  the  spray 
boom  should  be  raised  high  enough  to  permit  of  a  wide  and  even  distribution  of  the 
spray  material.    Presque  Isle,  Me. 

that  has  come  to  the  writer's  attention  of  benefit  derived  from 
thorough  spraying  with  Bordeaux  mixture  on  a  commercial  scale, 
is  reported  by  Dean*  for  the  years  1912,  1915  and  1917.  These 
were  years  in  which  severe  epidemics  of  late  blight  rot  occurred. 
In  these  three  seasons  Dean  sprayed  his  crop  14,  8  and  11  times, 
respectively,  and,  as  a  result  thereof,  secured  increases  over  un- 
sprayed plants  of  183,  200  and  213  bushels  per  acre.  It  should  be 
said  that  such  increases  are  possible  only  where  the  spraying  is 
thoroughly  done,  and  where  cultural  conditions  are  satisfactory  to 
the  production  of  a  large  crop. 

Spray  Equipment. — The  development  of  spray  equipment  has 
practically  kept  pace  with  that  of  the  chemist  in  the  manufacture 
of  new  fungicides  or  insecticides.     Broadly  speaking,  spray  equip- 


344 


FUNGICIDES  AND  INSECTICIDES 


meiit  may  be  roughly  classified  under  two  heads,  viz.,  liquid  and 
dust  sprayers.  Liquid  spray  equipment  may  in  turn  be  divided 
into  hand,  tractor,  and  gasoline-driven  pumps.  Hand  equipment 
may  consist  of  a  hand  atomizer,  bucket  pump,  knapsack  sprayer. 


Fig.   196.— a    l  \  j 
Manufacturing  Co. 


Fig.  197        .     . 
niounted  in  front  of  spray  tank, 


Spray   outfit  hauled  by    horses,   pump  operated  by 
Courtesyof  Bateman  Mfg.  Co. 


gasoline  engine 


auto-spray,  and  barrel-pump  sprayers.  The  tractor-driven  sprayers 
consist  of  one-  or  two-liorse  machines  of  from  50  to  over  100 
gallons  capacity,  the  pump  of  which  is  operated  by  being  geared 
to  one  or  both  wheels  of  the  spray  cart.  Such  machines,  when 
the  valves  are  properly  packed,  are  capable  of  developing  from  125 


SPRAY  EQUIPMENT 


345 


to  200  or  more  pounds  of  pressure.  Gasoline-driven  spray  equip- 
ment consists  of  spray  machines  hauled  by  horses  or  tractor  with 
gasoline-operated  pump.  With  such  machines  it  is  possible  to 
develop  from  200  to  300  pounds  pressure  per  square  inch.  With 
such  a  pressure  and  proper  nozzles  the  liquid  spray  is  broken 
into  such  fine  particles  that  it  resembles  a  fog  or  fine  mist.  When 
applied  in  this  manner,  properly  made  spray  materials  are  much 
more  effective  in  the  control  of  fungous  or  insect  pests  than  with 
a  pressure  of  75  to  125  pounds. 

Dust  sprayers  or  blowers  are  receiving  much  more  favorable 
attention  at  the  ])resent  time  than  in  the  past.     The  manufacturers 


A  traction-power  dust  spray  machine  in  action.    Courtesy  of  Niagara  Sprayer  Co. 


of  dust  blowers  are  constantly  perfecting  their  machines  and  we 
may  look  forward  to  a  much  larger  use  of  dust  sprays  in  the  future. 


(S'pray  Equipment  Classification. 
Liquid  Spray  Equipment 


Hand-operated  equipment 


Trac'tor-operated  equipment 


Gasoline-operated    eciuipment 


Hand-operated 
Tractor-operated 


Atomizer    (Fig.    190) 

Bucket  pumps   (Fig.  191) 

Knapsack   sprayers    (Fig.   192) 

Auto-spray  tanks    (Fig.   19.3) 

Barrel  pumps    (Fig.    194) 

Horse-drawn  sprayers  with  pump  oper- 
ated by  wheel  gears  (Figs.  195  and 
196) 

Spray  machine  hauled  hy  horses  or  trac- 
tor;   pump    operated    by  gasoline   en- 
gine   (Fig.    197) 
Dust  Spray  Equipment 

Atomizers 

Blow  guns 

Bellows 

One-  or  two-horse  tractor-driven  dust 
sprayers    (Fig.   198) 


346  FUNGICIDES  AND  INSECTICIDES 

QUESTIONS  ON  THE  TEXT 

1.  How  are  the  fungicides  and  insecticides  grouped? 

2.  Give  a   list  of  the  commonly  used   preparations   for   foliage   diseases. 

3.  What    are    the    two    commonly    employed    fungicides    used    for    tuber 

disinfection? 

4.  What  are  some  of  the  insecticides  used  for  the  control  of  leaf-chewing 

insects? 

5.  What  three  insecticides  are  recommended  for  sucking  insects? 

6.  What  is  recommended  for  tuber-infesting  insects? 

7.  Give  the  steps  in  discovery  and  development  of  Bordeaux  mixture. 

8.  What  is  the  present  standard   formula  for  use  on   potatoes? 

9.  What  constitutes  a  good  Bordeaux  mixture?     A  bad  Bordeaux  mixture? 

10.  Upon  what  does  the   fineness   of  the  precipitate  depend? 

11.  What   happens   when    the    milk   of    lime    is    added    to    a    concentrated 

copper    solution? 

12.  To  what  is  improperly  made  Bordeaux  mixture  largely  due? 

13.  What   are    the   advantages    of    a    convenient    spray    mixing   platform? 

14.  What  is  meant  by  a  gravity  system  of  Bordeaux  mixing?     How  does 

it  help? 

15.  What  are   stock   solutions?     How  are   they   prepared? 

16.  In  what  way  can  maximum  results  be  obtained  from  a  properly  made 

Bordeaux  mixture? 

17.  In  localities  where  late  blight  is  common,  when  should  spraying  begin? 

18.  Discuss  Bordeaux  paste  and  dry  Bordeaux  and  their  uses. 

19.  Compare  Pyrox  as  a  fungicide  with  Bordeaux  mixture. 

20.  Is  bug-death  etjual  to  Bordeaux  mixture  as  a  fungicide? 

21.  What  fungicides  are  employed  in  disinfecting  seed  potatoes? 

22.  Give  formula  for  the  preparation  of  the  two  solutions  and  the  time 

of  immersion  for  black  scurf. 

23.  Should  the  seed  stock  be  treated  before  or  after  cutting? 

24.  Compare    leaf-chewing   insects   and    sucking   insects    in    their    ease    of 

control. 

25.  What  is  Paris  green? 

26.  How  is  it  usually  employed,  and  in  what  strength? 

27.  When  employed  as  a  liquid  spray,  what  precaution  should  be  observed 

in  order   to  avoid   foliage   injury? 

28.  How  may  the  dry  powder  be  most  readily  mixed  with  water? 

29.  Give  directions  for  mixing  and  use  as  a  dust. 

30.  When  is  the  best  time  to  apply  dust  sprays  ? 

31.  What  is  arsenate  of  lead?     How   is   it  manufactured? 

32.  Compare  the  powder  and  the  paste  forms,  and  give   relative  amounts 

to  use. 

33.  What  is  calcium  arsenate,  and  how  does   it   compare   in   effectiveness 

with  arsenate  of  lead? 

34.  Compare  the  arsenoid  insecticides  with  arsenate  of  lead  in  effectiveness. 

35.  How  does  arsenite  of  zinc  compare  in  effectiveness  with  arsenate  of  lead? 

36.  How  are  sucking  insects  controlled? 

37.  What  are  the  three  commonly  employed  contact  insecticides? 

38.  What  is  black-leaf  40?     How  used? 

39.  How  is  kerosene  emulsion  prepared? 

40.  Of  what  value  is  whale-oil  soap  in  combating  sucking  insects? 

41.  Upon    what   does    the   value    of    ccmtact    insecticides    largely    depend? 


REFERENCES  CITED  347 

42.  What   results  were  secured  at  the  Vermont   Station   from  the  use  of 

Bordeaux  mixture? 

43.  What  results  were  secured  at  the  New  York  State  Station? 

44.  What  increases  did  Dean  secure  from  spraying? 

45.  How  may  liquid  spray  equipment  be  classified? 

46.  Describe   each   group   or   class   of   spray   equipment. 

47.  What  types  of  dust  spi-ayers  have  we? 

QUESTIONS  AND  EXERCISES  SUGGESTED  BY  THE  TEXT 

1.  Make  a  list  of  combined   troubles  for  which   we   should   use  combined 

sprays — insecticides  and  fungicides. 

2.  Give  the  combined  sprays  to  use  in  each  case. 

3.  Make  a  list  of  the  diseases  and  insects  which  are  likely  to  give  trouble 

to  local   crops. 

4.  Make  a   season's   spray   calendar   showing  the  troubles,   remedies   and 

times  for  use  in  your  region. 

5.  Inquire  from  local  growers  and  determine  the  numbers  of  applications 

of  sprays  for  the  worst  enemies. 

6.  Make  a  local  study  to  determine  the  degree  of  effectiveness  of  various 

treatments  and   materials   tried   by   growers. 

7.  Make  a  collection  of  materials  described  in  this  chapter. 

8.  Make    up    small    quantities    of    stock    solutions    of    Bordeaux. 

9.  Make  good  Bordeaux,  and  bad  Bordeaux.     Compare. 

References    Cited 

1.  Arthxir,  J.  C.     1897.     Formalin   for  prevention  of  potato  scab.     Jnd. 

ma.  Bui.  65,  June,  1897. 

2.  Bird,   R.   M.      1905.      Directions   for   making   Bordeaux  powder.      Mo. 

Bta.  Circ.  Inform.  20:   1-4,  April,  1905. 

3.  Britton,   W.   E.      1918.      Insects   attacking   the   potato    crop   in   Con- 

necticut.    Conn.    (New  Haven)    Sta.  Bui.   208:    117. 

4.  Dean,   Daniel.      1918.     Potato   spraying  as   a   war   "bit."     The  Pot. 

Mag.  1 :  3,  4,  20,  July,  1918. 

5.  FoKBusH,  E.  H.,  and  C.  H.  Ferxald.     1896.     The  Gypsy  Moth   (Proth- 

eria  dispar  Linn.)     Mass.  Bd.  of  Agr.  Spec.  Rpt.  1896:   141-142. 

6.  Graf,  J.   E.     1917.     The  potato  tuber  moth.     U.  H.  Dept.  Agr.  Bui. 

427:  20. 

7.  LuTMAN,   B.   F.      1911.      Plant  diseases.     Twenty  years   spraying   for 

potato  diseases.     Yt.  Hta.  Bui.  159:   225-247,  May,  1911. 

8.  MiLLARDET,   A.      1885.      Annates   d'    I'   8oc.   d'Agr.   d'    V    Gironde:    73, 

April,  1885. 

9.  Morse,  W.   J.      1900.      Experiments   with   insecticides   upon   potatoes. 

Me.  Sta.  Bul.  68:   177-179,  1900. 


chai>t]!:h  xviii 

industrial  uses  of  the  potato  in  america 
and  foreign  countries 

The  value  of  any  food  crop  for  industrial  purposes  and  par- 
ticularly a  perishable  one,  is  largely  determined  by  the  cheapness 
of  its  production ;  its  chemical  composition ;  the  number  of  valuable 
constituents  embodied  in  it ;  the  ease  with  which  these  elements 
may  be  converted  into  commercial  products;  and  last,  but  by  no 
means  least  important,  the  market  outlet  for  its  products. 

Constituents  of  the  Potato. — Chemical  analysis  of  the  potato 
shows  that  it  contains  approximately  75  to  80  per  cent  of  water, 
14  to  20  per  cent  of  starch  (occasionally  this  amount  may  reach 
23  to  25  per  cent),  1.5  to  2  per  cent  of  proteins,  and  2  to  3  per 
cent  of  fibre  and  mineral  salts  or  ash.  Its  value,  both  as  a  food 
and  in  the  industries,  is  due  to  its  starch  content.  Starch  occurs 
in  many  other  crops  besides  the  potato,  of  which  the  most  important 
commercially  are  corn,  cassava,  rice,  sago,  arrow-root,  and  wheat. 

Potato  Products. — Thus  far,  the  chief  manufactured  products 
consist  of  potato  starch,  potato  flour,  dried  or  deliydrated  potatoes, 
dextrine,  glucose,  dextrose  or  starch  sugar,  alcohol  and  lactic  acid. 
There  are,  doubtless,  other  possible  uses  of  potatoes. 

The  process  of  starch  manufacture  is  a  relatively  simple  one 
consisting  of  thoroughly  washing  the  potatoes;  grinding  or  grat- 
ing them  into  a  fine  pulp ;  wasliing  the  starch  from  the  fibrous 
material  of  the  potato  through  fine  sieves;  collecting  it  in  large 
vats,  where  by  changes  of  water  the  impurities  are  separated  from 
the  starch.  The  starch  settles  to  the  bottom  of  the  vat,  from 
whence,  after  the  liquid  has  been  drawn  off,  it  is  removed  to  the 
drier  and  subjected  to  heated  air  until  the  moisture  content  is 
reduced  to  about  18  per  cent. 

The  requirements  for  starch  manufacture  on  a  commercial 
scale  are  an  abundant  supply  of  pure  water,  a  clieap  l)ut  commodi- 
ous l)uilding,  having  a  reasonable  storage  capacity,  conveyors  to 
convey  the  potatoes  to  the  washer  and  grinder,  sieves  for  separating 
the  fibrous  parts  from  the  starch,  several  settling  tanks  of  rather 
large  capacity  to  purify  the  starch,  .and  a  drier  ])rovided  witli  steam 
or  flue  heat  for  drying  the  starch. 
348 


DOMESTIC  PRODUCTIOxN  OF  POTATO  STARCH  349 

The  dried  starch  may  he  marketed  in  200-pound  sacks  or  500- 
pound  wooden  casks. 

Starch  Yields. — The  average  yield  oC  commercial  starcli  from 
cull  potatoes  in  the  United  States  is  ai)proximately  15  per  cent 
of  the  weight  of  the  raw  material,  that  is  15  pounds  per  hundred- 
weight of  potatoes,  or  9  pounds  per  bushel.  The  yield  from  good, 
sound,  well  ripened  tubers  of  varieties  averaging  20  per  cent  of 
starch  is  correspondingly  greater. 

Uses  of  Potato  Starch. — Tlie  uses  or  connnercial  outlets  for 
l)otato  starch,  or  in  fact  any  starch,  may  be  roughly  divided  into 
three  classes:  (1)  for  edible  purposes;  (2)  for  laundry  purposes; 
(3)   for  manufacturing  purposes. 

1.  Starches  are  used  for  edible  purposes  in  ])ud(lings,  confection- 
ery, pastry,  and  as  a  stiffener  for  ice  cream,  custard,  i>ie  fillings, 
and  in  sausage  and  blood  ])udding  making.  For  the  last  two 
mentioned  products  potato  starch  is  considered  far  superior  to 
other  starches,  on  account  of  its  greater  swell  or  ex])ansive  power, 
and  the  firmness  that  it  imparts  to  the  product.  For  the  otlier 
]»urposes  corn  starch  is  more  largely  used  in  this  country,  chiefly, 
it  is  believed,  on  account  of  its  clieapness ;  and  partially,  no  doubt, 
due  to  the  fact  that  the  manufacture  of  high  grade  ])otato  starch 
has  not  heretofore  been  seriously  attempted  by  American 
starch  manufacturers. 

2.  The  use  of  potato  starcli  for  laundry  ])urposGs  may  be  re- 
garded as  practically  nil  in  this  country,  l)ut  it  has  a  large  use 
in  European  countries. 

3.  Tlie  superiority  of  potato  starcli  for  certain  manufacturing 
purposes  is  clearly  recognized.  Tlie  higher  viscosity  of  pro])erly 
dried  potato  starch  makes  it  more  desirable  to  use  in  the  sizing 
of  high  grade  fabrics.  In  lower  grade  fabrics  its  increased  price 
over  that  of  cornstarch  makes  its  use  more  or  less  prohibitive. 
It  is  generally  admitted  that  potato  starch  makes  the  best  grade 
of  dextrine  now  produced. 

Domestic  Production  of  Potato  Starch. — The  most  inii)ortant 
use  that  has  yet  been  made  of  the  potato  in  this  country,  in  an 
industrial  sense  at  least,  is  that  of  the  manufacture  of  starch.  The 
normal  production  of  starch  approximates  from  20  to  25  millions 
of  pounds.  According  to  data  published  by  the  United  States 
Tariff  Commission  in  1919,  tlie  number  of  establishments  reporting 
the  manufacture  of  starch  had  decreased  from  131  in  1904,  to  110 


350 


INDUSTRIAL  DSES  OF  THE  POTATO 


ill  1909,  and  82  in  1914.  Potato  starch  is  largely  manufactured 
in  Maine,  Wisconsin,  and  Minnesota.  Maine  is  said  to  produce 
over  80  per  cent  of  the  total  potato  starch  output  of  the  United 
States;  and  Aroostook  County  is  the  principal  centre  of 
the  industry. 

The  price  paid  for  cull  stock  ranges  from  25  to  75  cents  a  barrel 
under  normal  conditions,  with  an  average  of  about  45  to  50  cents 
per  barrel   (165  pounds). 

The  following  data  for  1904,  1909  and  1914  are  from  figures 
taken  from  the  Census  of  Manufacturers;  while  those  for  1915- 
1918  were  compiled  by  the  cornstarch  producers,  and  taken  from  the 
Textile  American,  December,  1918: 

Production  and  value  of  potato  starch  and  cornstarch  in  the  United  States. 


Number 

Potato  starch 

Cornstarch 

Year 

of 

factories 

Pounds 

Value 

Pounds 

Value 

1904. . 

131 

27,709,400 

$924,476 

311,140,814 

$  8,878,450 

1909.. 

110 

24,873,415 

823,019 

638,825,366 

15,962,916 

1914.. 

82 

23,540,472 

718,006 

574,247,697 

13,784,654 

1915. . 

775,891,649 

1916.. 

868,916,578 

1917.. 

833,131,755 

1918. . 

481,761,893 

These  figures  indicate  that  a  little  over  three  million  bushels 
of  potatoes  \vere  used  in  the  manufacture  of  starch  in  1904, 
about  two  and  three-quarter  million  in  1909,  and  somewhat  less 
than  that  amount  in  1914,  or  less  than  one  per  cent  of  the  total 
crop  in  either  of  the  three  periods.  It  is  evident  from  these  data 
that  even  potato  starch  production  furnishes  but  a  relatively  in- 
significant outlet  for  the  potato  crop  of  this  country.  In  order 
to  produce  a  stabilizing  influence  upon  the  potato  industry,  indus- 
trial outlets  must  be  developed  that  have  the  possibility  of  using 
from  10  to  20  per  cent  of  the  crop. 

Foreign  Production  of  Potato  Starch. — In  Germany  it  is 
claimed  that  4  per  cent  of  the  total  j)otato  crop  is  used  in  the 
manufacture  of  starch.  While  this  does  not  seem  large  when  think- 
ing of  it  in  terms  of  our  domestic  crop,  it  assumes  a  different 
value  when  considered  on  the  basis  of  over  a  billion  and  a  half 


WHY  IMPORT  STARCH 


351 


bushel  crop;  it  means  that  it  would  require  one-sixth  of  our  crop 
to  offset  the  4  per  cent  of  the  German  crop.  The  following  data 
shows  the  production  of  German  potato  products  in  1910-11: 

German  -production  of  -potato  products,  1910-11. 


Kind  of  product 


Potato     Wet  starch 

Starch^^  Qj.y  gtarch  and  potato   meal 
[_  Dry  &  wet  washing  starch . . 

Potato  sago 

Potato  meal  (lump) 

Glucose 

Glucose  sirup 

Caramel 

Dextrine 

Soluble  starch 

Dried  pulp  (residue) 

Wet  and  steamed  pulp 


Total 


Quantity, 
pounds 

Value 

125,671,700 

$  1,424,192 

.383,019,708 

8,447,810 

7,948,905 

61,880 

5,277,592 

168,266 

826,725 

28,560 

21,940,400 

550,018 

124,332,385 

3,104,472 

9,673,123 

307,734 

49,310,288 

1,404,914 

3,602,096 

107,100 

27,804,630 

144,942 

513,556,940 

212,295 

1,272,964,498 

$15,962,184 

From  Vierteljahrshefle  Statistik  des  Deutschen  Reichs,  IH,  p. 114,  Berlin,  1914. 

Starch  Imports. — Prior  to  the  war,  Germany  and  the  Nether- 
lands supplied  practically  all  of  the  starch  imported  into  the 
United  States.  From  1909  to  1913,  the  imports  averaged  13,730,665 
pounds,  valued  at  $375,767;  and  from  1914  to  1918,  they  averaged 
15,143,778  pounds,  valued  at  $704,712.  During  the  war,  the 
imports  shifted  from  Germany  and  tlie  Netherlands  to  Japan  and 
Canada.  Figures  for  1917  and  1918  show  that  Japan's  exports 
of  potato  starch  to  this  country  were  18,008,066  and  21,806,975 
pounds  respectively,  with  a  valuation  of  $799,775  and  $1,494,131. 
The  total  im])orts  from  all  sources  during  these  two  years  were 
20,647,893,  and  23,852,145  pounds,  or  an  amount  in  1918  equal 
to  our  total  production  of  potato  starch  in  1914.  It  is  claimed 
that  approximately  95  per  cent  of  the  starcli  imported  into  the 
United  States  is  potato  starch. 

Why  Import  Starch? — The  question  might  well  be  raised  as 
to  the  economic  reasons  for  the  consumption  of  foreign-made  potato 


352  INDUSTRIAL  USES  OF  THE  POTATO 

starch  in  this  country.  There  is  but  one  logical  reason — the 
uncertainty  of  a  sufficiently  large  supply  of  cheap  potatoes  each 
season  to  make  possible  the  profitable  operation  here  of  a  starch 
factory.  The  only  seasons  in  which,  under  normal  conditions, 
it  is  possible  to  manufacture  starch  at  a  price  sufficiently  low  to 
keep  out  foreign-made  starch  are  when  there  is  an  over-])roduction; 
when  late  blight  rot  is  prevalent  in  those  sections  where  starch 
factories  are  located;  or  when,  from  one  cause  or  another,  there  is 
an  unusually  large  percentage  of  unsalable  stock.  In  seasons  when 
the  crop  is  short,  the  oidy  stock  available  is  that  which  cannot  be 
disposed  of  for  table  purposes.  European  countries  are  able  to 
produce  potatoes  at  a  sufficiently  low  cost  to  permit  the  starch 
manufacturers  to  buy  table  stock,  at  prices,  tliat  in  tliis  country 
would  mean  financial  ruin  to  the  growers. 

POTATO    FLOUR 

The  possibility  of  using  potato  flour  as  a  partial  substitute 
for  wheat  flour  in  bread  making  was  forcibly  brought  to  the  at- 
tention of  the  American  housewife  when  the  plea  was  made  by  the 
U.  S.  Food  Administration  to  conserve  wheat  flour  by  the  use 
of  substitutes.  Unfortunately,  the  scarcity  of  potato  flour  and 
its  relatively  higli  cost  as  compared  with  wheat  flour,  together  with 
unfamiliarity  in  its  use,  proved  to  be  too  great  an  obstacle  to  be 
overcome  in  such  a  comparatively  short  period  of  time.  The 
interest  awakened  in  its  possibilities  has  not,  however,  subsided  as 
will  be  noted  under  domestic  production. 

Potato  Flour  Manufacture. — In  order  to  manufacture  a  high 
grade  potato  flour  it  is  necessary  to  use  sound  stock.  It  does  not 
follow,  however,  that  it  must  necessarily  be  of  No.  1  grade.  In 
fact,  it  has  been  demonstrated  within  the  past  three  years  that  it  is 
perfectly  feasible  to  make  a  good  quality  potato  flour  from  sound 
No.  2  and  cull  stock.  In  seasons  of  over-production  it  offers  an 
outlet  for  the  surplus  table  stock,  thereby  preventing  a  total  loss 
to  the  grower. 

The  manufacture  of  potato  flour  requires  a  greater  initial  out- 
lay for  both  equipment  and  building  than  that  involved  in  the 
production  of  starch.  The  cost  of  building  and  equipping  what 
is  termed  a  single  unit  plant  requires  an  initial  expenditure  of  from 
$20,000  to  $30,000  or  more,  depending  upon  the  character  of  the 
building  erected,  and  the  amount  of  storage  space  ])rovided  for  the 
raw  material  and  the  manufactured  product. 


POTATO  FLOUR  MANUFACTURE  353 

The  machinery  consists  of  a  washer,  long  conveyor,  cooker,  two 
spiral  screw  conve^'ors,  flaking  machine,  blower,  grinding  mill, 
and  a  bolter. 

The  first  step  in  the  manufacture  of  potato  flour  is  identical 
with  that  involved  in  making  starch,  that  is,  the  potatoes  must  be 
thoroughly  washed.  After  passing  through  the  washer  they  are 
carried  by  a  belt  conveyor  to  the  steam  autoclave  or  cooker,  and  if 
an  especially  fine  product  is  desired,  Avomen  or  girls  are  stationed 
along  the  conveyor  to  cut  or  remove  all  unsound  or  sunburned  mate- 
rial. In  a  medium-sized  factory  the  steam  cooker  used  has  a  load 
capacity  of  from  750  to  800  pounds  of  potatoes.  At  240  degrees  F. 
it  requires  about  fifteen  minutes  to  cook  the  potatoes.  The  cooked 
tubers  pass  from  the  cooked  through  a  screw  or  ribbon  conveyor 
to  a  hopper  above  the  drying  cylinders  and  from  thence  they  pass 
through  a  set  of  rollers  Avhich  crushes  and  distributes  them  in  an 
oven,  thin  layer  on  the  surface  of  the  steam  heated  cylinder,  which 
in  the  course  of  a  single  revolution  removes  most  of  the  excess 
moisture,  and  imparts  enough  heat  to  the  potato  to  dissipate  still 
further  moisture.  The  thin  layer  of  potato  is  removed  from  the 
cylinder  by  means  of  flexible  knife  blades.  The  dried  flakes  are 
i-emoved  from  the  flaker  or  drier  by  means  of  a  screw  conveyor 
which  breaks  up  the  material,  and  it  is  then  elevated  to  a  bin  above 
the  grinding  mill.  The  flakes  are  then  ground  and  bolted,  and 
the  flour  sacked. 

The  ])otato  flour  thus  secured  by  this  process  is,  in  reality,  a 
cooked  product.  It  embodies  all  of  the  chemical  constituents  of 
the  potato  tuber,  and  thus  retains  all  of  the  mineral  salts,  which 
are  generally  regarded  by  dietitians  as  being  highly  necessary  to 
the  health  of  the  body.  In  this  connection,  it  is  very  desirable  to 
remember  that,  in  the  past,  a  large  ])ercentage  of  the  potato  flour 
offered  for  sale  in  this  country  was  really  a  ])otato  starch  flour, 
that  is,  starch  re-ground  and  bolted.  The  legality  of  such  naming 
has  been  questioned,  and  a  ruling  rendered  which  makes  it  a  mis- 
demeanor to  brand  potato  starch  as  potato  flour.  The  justice  of 
such  a  ruling  is  apparent  to  all.  Potato  starch  flour  is  practically 
pure  starch.  All  the  mineral  salts  and  protein  compounds  were 
lost  in  the  manufacture  of  the  starch ;  furthermore,  it  is  not  a 
cooked  product  and,  therefore,  even  though  its  composition  was 
identical,  it  would  still  give  different  results  when  used  for  the 
manufacture  of  bread. 
23 


354  INDUSTRIAL  USES  OF  THE  POTATO 

Domestic  Production. — Had  the  question  been  asked  prior 
to  the  war,  one  would  have  been  ol^liged  to  answer  that  no  genuine 
potato  flour  w^as  being  made  in  the  country.  In  1918,  however, 
there  were  five  potato  flour  factories  in  operation  having  a  com- 
bined production  of  two  and  a  half  million  pounds.  The  cessation 
of  the  war  has  in  part,  at  least,  removed  the  more  urgent  incentive 
to  develop  a  stable  potato  flour  industry.  Three  of  the  five  facto- 
ries operating  in  1918  are  controlled  by  a  large  corporation,  with 
sufficient  available  capital  to  enable  them  to  spend  considerable 
sums  in  the  education  of  the  public,  and  particularly  the  bakers, 
regarding  the  value  of  potato  flour  in  some  form  in  our  diet.  The 
following  quotation  is  from  an  editorial  in  the  February,  1920, 
issue  of  the  Potato  Magazine,  p.  20 : 

"The  manufacture  of  potato  flour  in  this  country  (United  States) 
is  due  to  become  an  important  factor  in  tlie  potato  industry.  The  Falk 
Company  of  Pittsburgh,  owning  flour  manufacturing  plants  in  Michigan, 
Maine,  Colorado,  Minnesota,  Wisconsin  and  Idaho,  recently  contracted 
with  the  growers  in  the  vicinity  of  its  Colorado  plant  to  deliver  all  of 
their  No.  2  potatoes  to  them  for  the  next  five  years.  For  these  No.  2's 
and  all  odd  sizes  and  shapes  that  will  stay  on  an  inch  and  a  quarter 
mesh  screen,  the  growers  will  receive  60  cents  per  100  pounds,  delivered 

at   the    mill While    establishing    these    mills    in    different 

commercial  potato-producing  sections,  the  company  has  not  been  unmindful 
of  the  necessity  of  creating  a  market  for  their  product.  It  has  issued 
a  number  of  attractive  pamphlets  telling  the  bakers  of  the  advantages  of 

potato    flour This   has    resulted    in   an    excellent   sale   for 

potato  flour — the  newest  potato  product  to  be  produced  in  the 
United  States." 

The  future  of  the  potato  flour  industry  depends,  in  large 
measure,  upon  the  ability  of  those  engaged  in  it  to  create  a  growing 
demand  for  the  flour;  and  to  secure  a  sufficient  supply  of  No.  2 
potatoes  to  enable  them  to  operate  their  factories  over  a  long  enough 
period  each  year,  thus  making  it  possible  to  place  their  product  on 
the  market  at  a  reasonably  low  ])rice.  Such  price  must,  of  neces- 
sity, be  somewhere  near,  though  probably  slightly  in  excess  of, 
wheat  flour. 

DEHYDRATED  POTATOES 

Through  dehydration  the  potato  may  be  converted  into  what 
is  commercially  known  as  dried,  sliced,  cubed,  shredded,  or  riced 
potatoes.  When  intended  for  human  food,  all  dehydration  methods 
involve  the  partial  or  complete  cooking  of  the  potato.    So  far  as 


DRIED,  RICED  POTATOES  355 

the  United  States  is  concerned,  it  is  a  war  industry  development. 
In  European  countries  and  Germany  in  particular,  the  desic- 
cation of  potatoes  for  human  use  or  stock  feed  purposes  has  long 
been  practised. 

Dried,  Sliced  Potatoes. — In  the  manufacture  of  dried,  sliced 
potatoes,  a  fair  sized  potato  is  necessary  in  order  to  secure  a  goodly 
percentage  of  reasonably  large  slices  when  dried.  The  first  step 
in  the  preparation  of  the  material  is  the  selection  of  sound  stock; 
the  next  is  the  thorough  washing  of  the  same;  the  tliird  step  in- 
cludes the  paring  of  the  tul)ers  which  is  accomplished  by  attrition 
in  a  power-driven  centrifugal  machine;  the  fourth  step  consists 
in  the  hand  examination  of  the  pared  tubers  and  the  removal  of 
all  parts  not  cared  for  by  the  parer;  the  freshly  pared  potatoes  are 
then  sliced  by  a  slicing  machine  which  cuts  them  into  slices 
approximately  one-eighth  to  one-fourth  of  an  inch  thick.  The 
sliced  potatoes  are  caught  on  wooden  trays  with  cloth  or  wire 
bottom  over  which  they  are  spread  in  a  thin  layer.  They  are  then 
put  into  a  large  steam  chest  or  autoclave  for  a  few  minutes,  just 
long  enough  to  cook  them  sufficiently  so  that  they  will  not  turn  dark 
when  being  desiccated.  The  trays  are  then  placed  in  a  drying 
tunnel  or  chamber  in  which  the  slices  quickly  dry.  Success  or 
failure  in  the  manufacture  of  dried,  sliced  potatoes  is  dependent 
upon  the  care  exercised  in  each  successive  step  of  the  process.  A 
properly  made  product  should  retain  its  color,  a  light  amber  or 
straw  color,  and  when  placed  in  water  should  swell  to  its  original 
size  and  at  the  same  time  be  firm  and  brittle  rather  than  pasty 
and  leathery. 

Dried,  Cubed  and  Shredded  Potatoes. — In  the  manufacture 
of  dried,  cubed  or  shredded  })otatoes,  the  same  processes  are  fol- 
lowed as  in  drying  sliced  potatoes,  unless  they  are  intended  for 
stock  feed,  in  which  case  they  may  be  dried  by  direct  heat  in 
flue  gases. 

Dried,  Riced  Potatoes. — The  production  of  dried,  riced  pota- 
toes differs  from  dried,  sliced  potatoes  only  in  the  later  stages  of 
manufacture.  Its  preparation  is  the  same  up  to  the  point  of 
slicing ;  unless  the  tubers  are  large  they  are  cooked  whole ;  on  re- 
moval from  the  steam  chest  they  are  emptied  into  a  large  power- 
operated  press,  where  a  large  plunger  forces  the  cooked  product 
through  a  perforated  metal  plate.     The  finer  the  perforations  are 


356 


INDUSTRIAL  USES  OF  THE  POTATO 


in  the  plate  the  more  attractive  will  be  the  product  made.  A  very 
large  proportion  of  the  product  turned  out  by  American  manufac- 
turers during  the  war  was  riced  through  perforations  at  least 
three-eighths  of  an  inch  in  diameter.  The  riced  product  was  col- 
lected on  tra3's,  similar  to  those  used  in  making  dried,  sliced  pota- 
toes, and  placed  in  drying  tunnels.  When  ])artially  dry  they  arc 
removed,  and  run  through  a  machine  that  breaks  up  the  shreds 
into  shorter  lengths;  after  this  they  are  again  returned  to  the 
drier,  and  left  until  a  certain  stage  of  dryness  has  been  reached 
that  Avill  insure  long  keeping.  This  product  was  largely  used 
in  vegetable  soup  mixtures. 

Domestic  Production. — It  is  claimed  that  in  1918  there  were 
sixteen  drying  plants,  in  the  United  States,  engaged  in  producing 
dehydrated  potatoes,  with  a  combined  output  of  7  million  pounds. 
Upon  the  cessation  of  hostilities,  most  of  the  large  orders  for 
dehydrated  potatoes,  placed  Avith  these  manufacturers,  were  can- 
celled, wdth  the  result  that  this  branch  of  the  potato  industry  bids 
fair  to  languish  and  die.  The  only  possible  demand  that  is  now 
likely  to  be  made  for  dried  potato  products  will  be  for  the  higher 
grade  of  dried,  riced  potatoes,  that  is,  those  that  have  been  passed 
tlirough  a  very  fine  ricer,  and  have  been  so  handled  as  to  preserve 
a  bright  color.  Such  a  product  is  easily  prepared  for  table  use, 
either  as  mashed  potatoes,  or  for  soup. 

Foreign  Production. — The  following  statistics  on  the  German 
potato-drying  industry,  and  several  other  potato  products  for  the 
years  1908  to  1911,  published  in  Berlin  in  1911,  indicates  the 
extent  of  the  industry  in  pre-war  times. 

German  Potato-drying  JnduHiry. 


Total 
number 
factories 

Factories  using 

Am't.  domestic 

peeled 
potatoes 

unpeeled 
potatoes 

and  foreign 
potatoes  used 

1908-09 
1909-10 
1910-11 

170 
254 
327 

I 

4 

164 
246 
323 

5,898,774  bu. 
12,222,302  bu. 
15,345,485  bu. 

Other  German  Potato  Products. 

Products 

Cut  and  sliced 

Flakes  and  meal 

All  others 

Total 

1908-09 
1909-10 
1910-11 

14,263,762  lbs. 
35,163,370  lbs. 
31,878,516  lbs. 

77,072,816  lbs. 
157,143,888  lbs. 
204,057.776  lbs. 

330,690  lbs. 
793,656  lbs. 
661,380  lbs. 

91,667,268  lbs. 
193,100,914  lbs. 
2.36,597,672  lbs. 

GLUCOSE  PRODrCTION  357 

nEXTUIXE,    (iUTOSE     AND    .\L('OFH)L    IMiODrCTIOX 

Dextrine. — Tliis  is  u  jjroduct  oi'  starch  obtained  by  heating  it, 
either  alone  or  with  a  diluted  acid.  It  is  regarded  by  some  as  an 
intermediate  product  between  starch  and  glucose.  Dextrine  is 
soluble  in  water  and  possesses  strong  adhesive  properties.  It  is  sold 
on  the  market  under  the  names  of  potato  dextrine,  corn  dextrine, 
tapioca  dextrine,  British  gum  and  burnt  starch.  The  last  two 
terms  are  generally  applied  to  the  cruder  product. 

Method  of  Manufacture  of  Dextrine. — As  previously  noted, 
dextrine  is  a  ])rodnct  ol'  heated  starch,  or  of  starch  treated  with 
dilute  acid.  It  is  usually  made  by  heating  starch  in  an  oil  bath 
or  steam  jacket.  When  acid  is  used,  the  starch  is  moistened  with 
dilute  acid  and  then  air-dried ;  or  else  it  is  heated  at  a  low  tem- 
perature and  finally  the  finely  ground  product  is  placed  in  a  suit- 
able oven,  heated  with  steam.  Continuous  stirring  is  necessary  to 
insure  a  perfect  mixture.  Acid-treated  starch  usually  makes  a 
lighter  colored  dextrine,  but  the  sugar  it  contains  lessens  its  ad- 
hesive properties.  A  loss  of  some  20  to  25  per  cent  is  involved 
in  the  conversion  of  starch  into  dextrine.  This  loss  is,  in  part, 
compensated  for  through  the  absorption  of  moisture  by  the  dextrine. 

It  is  claimed  that  dextrine  made  from  potato  starch  has  a  greater 
adhesive  power  than  that  from  other  starches,  and  is  said  to  be 
generally  preferred  in  the  textile  trades.  It  also  makes  a  very 
satisfactory  product  for  gumming  envelopes  and  stamps. 

Domestic  Production  of  Dextrine. — The  United  States  now 
possesses  the  largest  ])lants  for  the  manufacture  of  dextrine.  Prior 
to  the  war  little,  if  any,  potato  dextrine  was  manufactured,  produc- 
tion being  limited  almost  entirely  to  corn  dextrine. 

In  point  of  value,  potato  dextrine  commands  the  highest  price 
and  corn  dextrine  the  lowest.  In  1914,  imported  potato  dextrine 
brought  six  to  seven  cents  per  pound ;  the  domestic  article  sold  for 
five  and  one-half  to  seven  cents  and  British  gum  at  three  and  one- 
eighth  to  three  and  one-quarter  cents;  while  corn  dextrine  ranged 
from  three  to  three  and  one-half  cents  per  pound.  In  the  latter 
part  of  1918,  domestic  potato  dextrine  quotations  showed  that  the 
price  had  advanced  to  twenty  cents  per  pound.  The  tariff  on 
dextrine,  (March,  1920),  was  three-fourths  of  a  cent  per  pound. 

Glucose  Production. — So  far  as  known,  potato  glucose  is  not 
manufactured  in  the  United  States,  corn  being  used  instead  of  the 
potato.  Potato  glucose  is  manufactured  on  a  rather  large  scale 
in  Europe  from  potato  starch. 


358  INDUSTRIAL  USES  OF  THE  POTATO 

Alcohol  Production. — The  production  of  alcohol  from  potatoes 
is  nowhere  so  extensively  practised  as  in  Germany.  This  statement 
is  well  substantiated  by  the  number  of  farm  and  industrial  stills 
that  were  in  operation  in  that  country  in  1911.  Skinner  says^ 
that  on  this  date  there  were  5,577  farm  stills  and  17  industrial 
stills,  used  principally  for  the  extraction  of  alcohol  from  potatoes; 
against  7,626  farm  stills  and  710  industrial  stills,  used  chiefly  for 
the  extraction  of  alcohol  from  grain.  Kremers  states^  that  there 
are  about  6,000  agricultural  potato  distilleries  in  operation  in  the 
German  Empire,  4,000  of  which  represent  one  of  the  chief  activities 
of  the  respective  farms,  whereas  the  remaining  2,000  have  a 
secondary  place. 

THE  NEEDS   OF  THE   POTATO   INDUSTRY 

The  successful  development  of  any  great  industry  is  wholly 
dependent  upon  the  demand  that  may  be  created  for  its  product 
or  products.  A  business  having  but  one  outlet  for  its  product 
has  a  much  smaller  chance  of  attaining  to  as  large  proportions 
as  one  that  has  several.  Many  industries  have  been  made  im- 
mensely profitable  through  the  by-products,  developed  from  mate- 
rials that,  in  the  early  stages  of  the  industry,  had  been  regarded  as 
waste  products.  The  meat  industry  of  this  country  furnishes  an 
excellent  illustration  of  what  might  be  practically  considered  the 
last  word  in  tlie  utilization  of  waste  products.  The  well-known,  but 
nevertheless  trite,  remark  that  the  large  meat  packing  houses 
utilize  everything  but  the  squeal  of  the  hog,  illustrates  in  a  most 
forceful  manner  the  business  thrift  of  these  large  corporations. 
When  similar  principles  are  applied  to  the  utilization  of  agricul- 
tural food  crops,  a  long  step  will  have  been  taken  toward  the 
stabilization  of  production.  The  potato  industry  of  America  has 
urgent  need  of  such  a  stabilizing  influence;  in  fact,  until  outlets  are 
created  which  will  provide  a  market  for  the  culls,  and  the  surplus 
stock  in  seasons  of  over-production,  potato  growing  will  continue 
to  be  one  of  the  largest  gambling  enterprises  in  which  the  American 
farmer  can  engage.  The  gambling  element  in  this  crop  is  due 
to  the  fact  that,  practically  speaking  at  least,  tlie  i)otato  has  but 
one  outlet,  that  of  table  stock. 

Per  Capita  Consumption. — The  normal  per  capita  consump- 
tion of  potatoes  in  the  United  States  is  difficult  to  estimate  with  any 
great  degree  of  accuracy,  on  account  of  the  fact  that  production 


PER  CAPITA  CONSUMPTION  359 

varies  widely  from  year  to  year,  with  a  consequent  upward  and 
downward  movement  of  prices,  all  of  which  tends  to  curtail  con- 
sumption. One  way  of  estimating  the  per  capita  consumption  is 
to  take,  as  a  basis  for  computation,  the  average  annual  production 
of  the  United  States  for  the  five-year  period  1915-1919,  or  371,- 
708,600  bushels  and  divide  it  by  the  average  annual  population  for 
the  same  period,  which  we  will  assume  to  be  approximately  110 
millions  of  people;  this  gives  us  a  per  capita  average  of  a  little 
less  than  three  and  one-half  bushels.  But  such  a  figure  represents 
per  capita  production  and  not  per  capita  consumption.  To  arrive 
at  the  per  capita  consumption,  it  is  necessary  to  deduct  all  stock 
unfit  for  table  purposes,  all  diseased  and  frozen  stock,  to  make 
allowance  for  the  natural  and  inevitable  storage  shrinkage,  and  last 
but  not  least,  deduction  must  be  made  of  the  seed  necessary  to 
plant  the  ensuing  year's  crop.  While  it  is  difficult  to  make  exact 
estimates  of  the  percentages  ordinarily  involved,  it  is  believed  that 
the  figures  given  are  not  far  amiss  if  applied  over  a  series  of  years : 

Culls  or  unsalable  stock 10  per  cent. 

Diseased,  frozen  and  storage  shrinkage.    10  per  cent. 
Seed  for  ensuing  crop 10  per  cent. 

The  probability  is  that  the  first  two  percentage  figures  are  too 
low  rather  than  too  high.  The  last  estimate  may  be  regarded  as 
approximately  correct.  Deducting  30  per  cent  from  the  total  crop 
of  371,708,600,  leaves  260,196,020  bushels  available  for  consump- 
tion, a  trifle  over  two  and  one-third  bushels  per  year,  or  a  per 
diem  allowance  of  six  and  one-tenth  ounces  for  each  man,  woman 
and  child  in  the  United  States.  Contrast  this  with  a  per  capita 
consumption  of  seven  and  one-third  bushels  in  Germany,  an  amount 
almost  three  times  as  great  as  that  used  by  our  own  people.  As- 
suming that  the  figures  presented  are  approximately  correct,  it  is 
seen  that  70  per  cent  of  the  potato  crop  produced  in  the  United 
States  is  used  for  table  purposes.  In  Germany,  it  is  claimed  that 
only  28  per  cent  of  a  normal  crop  is  used  for  table  food.  The 
balance  of  the  crop  is  disposed  of  as  follows :  40  per  cent  is  fed 
to  live  stock;  12  per  cent  used  for  seed;  10  per  cent  for  industrial 
purposes;  and  the  remaining  ten  per  cent  is  regarded  as  waste, 
due  to  decay,  shrinkage  and  other  causes.  The  large  balance  of 
the  German  crop,  over  and  above  the  actual  requirements  for  table 
food  purposes  is  available  in  seasons  of  low  production  years,  for 


360  INDUSTRIAL  USES  OF  THE  POTATO 

human  food.  It  simply  means  that  a  lesser  amount  is  used  for 
industrial  purposes.  This  prevents  wide  fluctuations  in  prices, 
such  as  occur  in  the  United  States  when  there  is  a  short  crop. 

It  has  been  shown  in  a  previous  portion  of  this  chapter  that 
somewhat  less  than  one  per  cent  of  the  crop  of  this  country  is 
converted  into  starch,  and  that  we  have  the  beginnings  of  a  potato 
flour  and  possibly  a  potato  dextrine  industry.  Just  how  far  it 
may  be  possible  to  increase  all  three  of  these  industries  depends, 
to  a  considerable  extent,  upon  the  degree  of  protection  they  receive 
from  foreign  competition,  and  to  our  ability  to  reduce  the  cost  of 
production  by  increasing  the  j)er  acre  yield.  The  fact  should  not 
be  lost  sight  of  that  these  commodities  are  being  manufa(;tured 
out  of  the  cull  potatoes,  with  the  probability  that  it  will  be  some 
years  before  the  industrial  uses  of  the  potato  will  exceed  the  normal 
supply  of  unsalable  potatoes. 

Increased  Consumption  Desirable. — The  only  way  by  which 
the  consumption  of  potatoes  may  be  increased  is  to  produce  a  suf- 
ficient crop  each  season  to  guarantee  an  ample  supply  for  table 
purposes  at  a  price  commensurate  with  their  food  value.  This 
would  involve  a  large  over-j)roduction  during  favorable  years,  for 
which  a  profitable  outlet  would  have  to  be  created.  Alternate 
years  of  high  and  low  production,  with  their  consequent  wide  fluct- 
uation in  prices  are  detrimental  to  both  grower  and  consumer, 
as  well  as  to  the  industry  itself.  When  prices  are  high,  the  con- 
sumer substitutes  other  vegetables  or  vegetable  products,  and  thus 
gets  out  of  the  habit  of  eating  potatoes  each  day  as  a  regular  part 
of  his  or  her  diet.  Production  must  be  increased  through  the  use 
of  better  seed  and  improved  cultural  practices,  therel)y  securing 
larger  yields  per  acre  at  a  reduced  cost  per  bushel.  Consumption 
must  be  increased  through  a  steady  supply  of  good,  sound  potatoes, 
at  a  price  consistent  with  a  fair  profit  to  the  producer.  Production 
and  consumption  must  go  hand  in  hand  if  a  stable  industry  is  to 
be  built  up. 

Distribution. — Distribution  is  one  of  the  important  links  be- 
tween the  producer  and  the  consumer.  Heretofore,  the  processes  of 
distribution  of  produce  from  the  farm  to  the  door  of  the  consumer 
have  been  slow,  faulty  and  expensive  because  of  the  numerous  hands 
through  which  it  ordinarily  passes,  each  one  of  which  exacts  a 
toll,  not  always  in  keeping  with  the  service  rendered. 


POTATOES  AS  FEED  FOR  LIVESTOCK  361 

POTATOES  AS  FEED   FOll   LIVESTOCK 

The  possibility  of  making  greater  use  of  potatoes  as  a  feed  for 
livestock  should  not  be  overlooked.  It  is  difficult  to  grasp  the  fact 
that  German  farmers  feed  nearly  twice  as  many  potatoes  to  their 
farm  animals  as  the  United  States  produces.  Some  40  million 
hogs  are  largely  grown  and  fattened  on  potatoes  in  Germany.  If 
we  are  to  have  a  prosperous  and  stable  agriculture,  we  must  see 
to  it  that  there  is  no  unnecessary  waste.  Potatoes,  M'hen  cooked 
or  siloed  and  fed  with  grain,  make  a  reasonably  cheap  and  acceptable 
feed  for  swine  and  other  farm  animals,  though  cooking  is  not  neces- 
sary when  fed  to  cattle. 

Eound  and  Gore-  have  develoi)ed  a  cheap  and  satisfactory  method 
of  converting  cull  or  surplus  potatoes  into  silage.  They  summar- 
ize the  result  of  their  studies  as  follows : 

1.  "The  use  of  2  to  n  jter  cent  of  corn  meal,  mixed  with  cruslied 
potatoes,  insures  an  acid  fermentation,  which  converts  tlie  potiitoes  into 
silage. 

2.  This  work  may  l)e  done  upon  any  scale.  If  reasonalde  care  is  used, 
losses  should  be  negligible. 

3.  The  potatoes  should  first  be  washed,  and  then  cruslied  Ijy  passing 
them  through  an  apple  grater,  which  has  been  modified  by  substituting 
rows  of  blunt  spikes  for  the  grater  knives. 

4.  The  fermentation  requires  a  tight  receptacle,  which  may  be  a 
barrel,  vat,  pit  or  silo,  but  must  retain  the  potato  juice. 

5.  The  upper  surface  of  the  crushed  potato  should  first  lie  covered,  to 
a  depth  of  several  inches,  with  an  absor1)ent,  fibrous  substance  such  as 
straw,  corn-stalks  or  leaves;  then  closely  fitted  with  a  wooden  cover, 
weighted  down  by  stones,  until  the  surface  of  the  potatoes  is  barely  covered 
by  juice.     The  top  of  the  straw  and  the  board  cover  should  be  kept  dry. 

6.  Fermentation  begins  at  once.  With  -the  evolution  of  gas,  con- 
siderable pressure  develops,  which  should  be  controlled  by  extra  weights. 
After  a  few  days  this  pressure  disappears.  Acid  fermentation  continues, 
however,  for  two  or  three  Aveeks.  As  in  other  fermentations,  the  length 
of  time  necessary  is  directly  dependent  on  the  temperature. 

7.  The  resulting  potato  silage  is  refreshingly  acid  in  flavor,  free  from 
any  putrid  odors  and  of  aliout  the  consistency  and  appearance  of  the 
original  crushed  potato. 

8.  Potato  silage  is  eaten  freely  liy  cattle,  and  somewhat  less  readily  at 
first  by  hogs,  although  they  soon  learn  to  eat  it  " 

In  sections  where  there  are  no  starch  or  potato-flour  factories 
to  utilize  the  ciills  or  surplus  stock,  good  agriculture  demands  that 
some  provision  be  made  to  feed  them  to  livestock,  and  thereby  utilize 
their  feed  values,  thus  increasing  our  dairy  and  meat  j)roducts. 


362  INDUSTRIAL  USES  OF  THE  POTATO 

QUESTIONS  ON  THE  TEXT 

1.  What  determines   the   value   of  a   food   crop   for   industrial   purposes? 

2.  What  does  a  chemical  analysis  of  the  potato  reveal  as  to  its  constituents? 

3.  What  is  its  most  important  constituent? 

4.  In  what  other  crops  does  starch  occur  abundantly? 

5.  What  are  the  chief  manufactured  products  of  the  potato? 

(5.  From  what  portion  of  the  potato  crop  of  the  United  States  is  starch 
manufactured  ? 

7.  Describe  the  successive  steps  involved  in  the  manufacture  of   starch. 

8.  What  is  the  average  yield  of  commercial   starch   from  cull  potatoes? 
D.  What  are  the  commercial  outlets  for  all  kinds  of  starches? 

10.  What  are  the  chief  uses  made  of  potato  starch? 

11.  To  what  e.xtent  is  potato  starch  manufactured  in  the  United  States? 

12.  In  what  states  is  potato  starch  most  largely  manufactured? 

13.  Which  state  is  of  greatest  importance  and  what  per  cent  of  the  total 

output  is  made  in  this  state? 

14.  What    is    the    usual    or    normal    price    paid    for    potatoes    by    starch 

manufacturers? 

15.  How  many  starch  factories  were  in  operation  in  the  United  States  in 

1904,  1909  and  1914? 

16.  How  did  the  outpiit  of  potato  starch  compare  with  that  of  cornstarch 

during  these  periods  ? 

17.  About  how  many  bushels  of  potatoes  were  required  for  starch  purposes 

and  what  per  cent  of  the  total  crop  did  it  represent? 

18.  How  does  this  amount  compare  with  that  of  Germany? 

19.  What  proportion  of  our  crop  would  4  per  cent  of  the  German  crop 

represent? 

20.  How   extensive   are   the   imports    of    starch    into   the    United    States? 

21.  How  did  these  imports  shift  during  the  war? 

22.  What  economic  factors  are  involved  in  the  manufacture  of  a  constant 

supply  of  potato  starch? 

23.  When  did  the  American  public  first  become  interested  in  potato  flour? 

24.  Describe   the  processes   involved    in   the   manufacture   of    potato   flour. 

25.  Wliat  is  the  diflference  between  potato  flour  and  potato  starch  flour? 

26.  Upon    what    does    the    future    of    the    potato    flour    industry    depend? 

27.  What  are  the  ordinary  products  manufactured  from  the  potato  through 

the  process  of  dehydration? 

28.  How  is  the  industry  to  be  regarded  in  the  United  States? 

29.  Describe   the   processes   involved   in   the   manufacture    of    good,    dried, 

sliced  potatoes. 

30.  Describe  the  manufacture  of  dried,   riced  potatoes. 

31.  To    what    extent    were    dried    potato    products    manufactured    during 

the  war? 

32.  What  is  the  present  status  of  the  industry? 

33.  Of   what    commercial    importance    is    the    potato    drying    industry    in 

Germany?     In  the  United  States? 

34.  Describe   processes    involved    in    the   manufacture    of   potato   dextrine. 

35.  How  does  potato  dextrine  compare  in  value  with  that  of  dextrine  made 

from  other  starches? 

36.  Of  what  importance  is  potato  glucose  production  ? 

37.  In  what  country  has  potato  alcohol  production  become  an   important 

commercial   industry? 

38.  What  are  the  needs  of  the  potato  industry  in  the  United  States? 

39.  What  is  the  average  per  capita  production  in  the  United  States? 


REFERENCES  CITED  363 

40.  How  does  the  average  per   capita   consumption   in  the  United   States 

compare  with  that  of  Germany? 

41.  What   percentage   of   the   total   German   potato   crop   is   consumed   for 

table  purposes? 

42.  How  does   the   German  percentage   compare   with   that  of  the   United 

States  ? 

43.  How  is  the  balance  of  the  German  crop  iitilized? 

44.  How  does  the   large  excess   of  potatoes   over  and   above  the   needs  of 

the  German  people  for  table  purposes  tend  to  stabilize  the  price? 

45.  What   efl'ect   does   alternate   years   of   high    and   low   production    have 

upon  the  table  consumption  of  potatoes  in  this  country? 
40.  What  is  the  solution  of  the  problem  of  high  and  low  production  with 
its  consequent  price  fluctuations? 

47.  What  is  the  relation  of  distribution  to  crop  production? 

48.  iMong  what  other  lines  may  we  increase  potato  consumption? 

49.  Describe  the  process  of  making  silage  out  of  the  potato. 

EXERCISES  SUGGESTED  BY  THE  TEXT 

1.  Collect  a  set  of  samples  of  potato  products  and  preserve  them  in  glass 

jars  or  bottles. 

2.  Examine  potato  tissue  under  a  strong  microscope. 

3.  Draw  several  grains  of  potato  starch  showing  the  layers. 

4.  Grate   a    large   potato,    using   a   kitchen    vegetable   grater.      Hold    the 

material  in  a  cheesecloth  and  wash  thoroughly  in  a  dish  of  water 
to  remove  the  starch.  Allow  it  to  settle,  remove  the  water  and 
dry  the  starch. 

5.  Weigh  the   starch  from  a  given  weight   of  potato  and  determine  the 

percentage  of  starch. 

6.  Determine  the  percentage  of  water  in   a   potato   Ijy   weighing,   slicing, 

drying  and  weighing  again. 

References    Cited 

1.  Kremers,  E.     IGl/).     Agricultural  alcohol:   Studies  of  its  manufacture 

in  Germany.     U.  S.  Dept.  Agr.  Bui.  182:   14,  Feb.,  191;}. 

2.  Round,  L.  A.,  and  H.  C.  Gore.     1916.     A  preliminary  report  upon  the 

making  of  potato  silage  for  cattle  food.  Proc.  Third  Ann.  Meeting 
Pot.  Ass'n.  of  Am.:  75-79,  1916. 

3.  Skinner,  R.  P.     1914.     Utilization  of  potatoes.     U.  S.  Dept.  Commerce 

Spec.  Cons.  Rpt.  No.  64:   1-44,  1914. 


PART  II 

CHAPTER  XIX 
THE  BOTANY  OF  THE  POTATO 

The  potato  is  botanically  known  as  Solarium  tuberosum,  L., 
and  is  a  member  of  the  Solanacece  or  nightshade  family  of  plants. 
The  tomato,  eggplant  and  pepper  are  close  relatives  of  the  potato. 

In  discussing  the  genus  Solarium,  Baker-  claims  that  it 

"is  one  of  the  largest  genera  in  the  vegetable  kingdom.  About  900  names 
stand  in  the  botanical  books  as  species,  and  Benthara  and  Hooker  estimate 
that  probably  700  of  these  are  really  distinct.  Of  these  700  it  is  only  six 
that  grow  potatoes  at  all,  and  the  remainder  all  maintain  their  hold  in 
the  world,  as  most  plants  do,  by  means  of  their  flowers,  fruits  and  seeds." 
The  six  tuber-bearing  species,  according  to  Baker's  conclusions  (p.  504, 
505),  are:  (1)  Solanum  tuberosum,  L. ;  (2)  8.  Maglia,  Schlecht;  (3) 
8.  Commersoni,  Dunal;  (4)  8.  cardiophyllum,  Lindley;  (5)  8.  Jamesii, 
Torrey;    (6)   8.  oxycarpum,  Schiede. 

More  recent  studies  by  Bitter/  of  Bremen,  Germany,  have  re- 
sulted in  a  much  larger  list  of  tuber-bearing  species  than  is  con- 
tained in  Baker's  list.  An  enumeration  of  Bitter's  species,  as  well  as 
those  of  others,  is  not,  however,  considered  pertinent  to  the  present 
discussion.  It  is,  however,  thought  desirable  to  give  Baker's  descrip- 
tion {I.e.  p.  489),  made  from  the  living  plant,  of  a  typical  specimen 
grown  in  the  herbaceous  ground  at  Kew  Gardens,  England: 

Description. — "  Rootstock  bearing  copious  large  tubers.  Stems  stout, 
erect,  flexuose,  much  branched,  one  to  two  feet  long,  slightly  hairy, 
distinctly  winged  on  the  angles.  Leaves  pseudo-stipulate,  a  fully  developed 
one  about  half  a  foot  long,  with  seven  to  nine  finely  pilose,  oblong,  acute, 
large  leaflets,  the  side  ones  stalked  and  unequally  cordate  at  the  base, 
the  one  to  two  lowest  pairs  much  dwarfed,  leaving  a  naked  petiole  about 
an  inch  long,  the  rhachis  furnished  with  numerous  small  leaflets,  inter- 
spersed between  those  of  full  size.  Flowers  numerous,  arranged  in  com- 
pound terminal  cymes,  with  long  peduncles;  pedicels  hairy,  articulated 
about  the  middle  Calyx  hairy,  one-fourth  to  one-third  inch  long,  teeth 
deltoid-cuspidate,  as  long  as,  or  a  little  longer  than,  the  campanulate  tube. 
Corolla  dark  lilac,  subrotate,  nearly  an  inch  in  diameter,  pilose  externally; 
segments  deltoid,  half  as  long  as  the  tube.  Anthers  bright  orange-yellow, 
linear-oblong,  nearly  one-fourth  inch  long;  filaments  very  short.  Berry 
perfectly  globose,  smooth,  under  an  inch  in  diameter. 

The  potato  tuber  arises  as  a  terminal  enlargement  or  swelling 
of  a  thick,  and  usually  rather  short,  underground  stolon.     These 
364 


THE  BOTANY  OF  THE  POTATO 


365 


tuber-bearing  stolons  arise  from  what  above  ground  would  be  the 
axils  of  the  leaves,  on  the  main  stem  of  the  plant,  extend  more  or 
less  horizontally  outwards,  and  sooner  or  later  normally  swell  up 


Fig.  199. — Early  stage  of  tuber  development.    Note  special  tuber-bearing  stolons. 

at  their  tips  to  form  tubers   (Figs.  199  and  200).     In  this  con- 
nection, Eeed^  says : 

"That  these  structures  are  stems  is  shown  Ijy  their  origin  and  their  ana- 
tomical and  morphological  structure" 

Arthur^  describes  the  potato  tuber  as  follows : 

"The  potato  tuber  is  a  thickened  stem,  having  the  cells  mostly   filled 
with  starch  as  a  reserve  food  for  the  new  plants.     The  eyes  are  the  promise 


THE  BOTANY  OF  THE  POTATO 


of  the  future  branches.  The  skin  differs  from  the  surface  covering  of 
the  rest  of  the  plant  by  being  formed  of  a  layer  of  delicate  cork  with  its 
accompanying  lentioels,  and  the  fibrous  framework,  as  well  as  the  pith, 
is  continued  from  the  leaf-bearing  stems  into  the  tuber  with  relatively 
little  change.  Liquids  move  from  part  to  part,  most  readily  through  the 
fibrous  tissue,  and  not  through  the  proper   pith.     This   indicates   that   in 


Fig.  200. — A  more  advanced  stage  uf  tuber  development  than  in  Fig.   199. 


cutting  seed  potatoes,  the  movements  of  the  nutrient  sap  in  germination 
have  no  bearing  upon  the  question  of  the  best  form  of  the  pieces,  except 
that  they  should  reach  deep  enough  to  include  the  wood  ring." 

In  Baker's  technical  description  of  the  plant  he  says  that  the 
stem  is  distinctly  winged.  This  statement  was,  of  course,  based 
on  the  plant  he  described  and  does  not  necessarily  apply  to  all  of 


PARTS  OF  A  POTATO  TUBER  367 

our  cultivated  varieties,  as  many  of  them  are  not  winged  or  if  they 
are,  it  is  very  slight.  The  same  explanation  should  be  made  re- 
garding the  color  of  the  flowers,  which,  while  constant  in  any  given 
variety  or  group  of  varieties,  is  not  constant  with  respect  to  all 
varieties.  It  is  well  known  that  the  color  of  the  flower  may  vary 
with  the  variety,  from  the  delicate  creamy-white  through  all  shades 
of  pink,  rose-purple,  lavender  and  blue.  In  fact,  many  of  them 
are  extremely  attractive  in"  color  and  large  in  size,  especially  in 
seedlings  resulting  from  South  American  crosses. 

Parts  of  a  Potato  Tuber. — The  potato  tuber  may  be  anatom- 
ically divided  into  four  rather  distinct  parts  or  zones  which  are 
morphologically  known  as:  (1)  The  envelope  or  skin;  (2)  the 
cortical  layer;  (3)  the  external  medullary  area,  and  (4)  the 
internal  medullary  area.  The  delimitations  of  1  and  2  are  clearly 
defined  but  that  of  3  and  4  are  not  so  clearly  separable.  They 
are  usually  defined  as  follows : 

1.  The  envelope  or  skin  comprises  the  corky  or  outer  cover- 
ing of  the  tuber,  corresponding  to  the  bark  of  an  above-ground  stem. 

2.  The  cortical  layer  consists  of  the  peripheral  zone  immedi- 
ately beneath  the  skin.  This  zone  or  layer  may  vary  from  one- 
eighth  to  one-half  an  inch  in  thickness.  It  is  denser  and  less 
translucent  than  the  external  medullary  area,  from  which  it  is 
separated  by  a  well-defined  line  or  ring  of  fibro-vascular  bundles. 
If  exposed  to  light,  this  part  of  the  tuber  quickly  turns  green,  and 
acquires  a  distinctly  acrid  taste  due  to  an  accumulation  of  a 
poisonous  substance,  chemically  known  as  solanin. 

3.  The  external  medullary  area  embraces  the  outer  portion 
of  the  strictly  fleshy  part  of  the  tuber.  It  is  generally  interpreted 
as  including  the  denser  portion  of  the  medullary  area. 

4.  The  internal  medullary  area  includes  the  Avatery  and  more 
translucent  central  part  of  the  tuber. 

Langworthy^  states  that,  according  to  determinations  made  in 
the  Department's  laboratories,  the  actual  skin  of  the  potato  rep- 
resents about  2.5  per  cent  of  the  whole,  the  cortical  layer  about 
8.5  per  cent,  leaving  89  per  cent  for  the  medullary  areas.  This 
difl'ers  quite  appreciably  from  the  percentages  given  by  Condon 
and  Bussard*  as  will  be  noted  from  the  following  figures: 

Envelope  or  skin 8.79  per  cent. 

Cortical  layer    .36.19  per  cent. 

External  medullary  area 34.17  per  cent. 

Internal  medullary  area 14.96  per  cent. 


368  THE  BOTANY  OF  THE  POTATO 

From  the  botanical  standpoint,  these  variations  in  percentages 
are  of  no  material  consequence  to  the  present  discussion.  It  is, 
perhaps,  permissible,  however,  to  say  that  from  the  chemical  stand- 
point the  relative  proportion  of  these  four  parts  of  the  potato  is 
vitally  important,  as  it  is  materially  concerned  with  its  food  value. 
The  cortical  layer  is  of  especial  interest,  because  it  contains,  in 
addition  to  starch,  a  higher  ])ercentage  of  mineral  matter,  soluble 
carbohydrates  and  nitrogenous  matter,  as  well  as  of  acid  sub- 
stances, than  do  the  other  })arts  of  the  tubers. 

QUESTIONS  ON  THE  TEXT 

1.  Under  what  name  is  the  potato  hotanioally  known? 

2.  Is  the  Solantim   group  a  large  one?     Name  common  garden   crops  of 

this    group. 

3.  How  many,  according  to  Baker,  are  tuber-bearing?     Name  them. 

4.  Does  Dr.  Bitter  concur  with  Baker  in  his  limitation  of  tuber-bearing 

species  ? 

5.  What  is  the  potato  morphologically? 

6.  What  can  you  say  regarding  the  winged  stems? 

7.  Name  the  four  parts  of  a  potato  tuber. 
S.  Deseri!)e  eacli. 

EXERCISES  ON  THE  TEXT 

1.  Compare  the  flowers  of  potato,  tomato,  eggplant  or  others  of  the  family 

and  note  likenesses. 

2.  Read  the  floral  descriptions  in  a  good  botany  book  and  compare  with  the 

specimens. 

3.  Study   the   morphology   of   the   undergroimd   parts   of   a   potato   plant 

and  show  that  underground  stems  do  exist. 

4.  Preserve  some  of  these  underground  parts  with  small  tubers  in  a  glass 

jar.     Use  two  per  cent  formalin  water. 

5.  Find  specimens  showing  the  winged  stems  and  others  where  the  wings 

are   less   prominent. 

6.  Make  sections  of  potato  tubers  and  point  out  the  four  parts. 

7.  Draw  and   label   parts. 

References  Cited 

1.  Arthur,  J.  C.     1888.     Structure  of  the  potato  tuber.     Ind.  Sta.  Bui. 

If),  1888. 

2.  Bakkk,  J.  G.     1884.     Review  of  the  tuber-bearing  species  of  Solannm. 

Jovr.  Linn.  ISoc.  of  Bot.     (London)   20:  489-507,  1884. 
.3.  Bitter,  G.     1912-1914.     Solana  nova  vel  minus  cognita.     Repertoriiim 
8p.  Nov.  Regni  Vegetal).   10:   520-565;   11:    1-18,  202-237,  241-200. 
349-394,  431-473,  481-491,  5Gl-5(iO;    12:    1-10,  49-90,   136-162,  4.33- 
467,  542-555;    13:   88-103,   169-173,  1914. 

4.  CouDON,  H.,  and  L.  Bussard.     1897.     Recherches  sur  la  pomme  de  terre 

alimentaire.     Ann.  »*?c.  Agron.     2nd.   ser.  3rd  ann.    1:    261,   1897. 

5.  Lanc.wortiiy.  C.  F.     1917.     Potatoes,  sweet  potatoes  and  other  starchy 

roots  as  food.     U.  8.  Dept.  Agr.  Bui.  468:  1-28,  Jan.,  1917  (seep.  24). 

6.  Reed,  F.     1910.     Anatomy  of  some  tubers.     Ann.  Bot.     (London)   24: 

537-548,  pis.  2,  4  dgiiis. 


CHAPTER  XX 
ORIGIN  AND  EARLY  HISTORY  OF  THE  POTATO 

Origin, — For  over  a  century  the  question  of  the  origin  of  the 
potato  has  occupied  the  minds  of  many  botanical  explorers  and  nat- 
uralists. While  scientists  are  agreed  that  the  potato  is  indigenous 
to  South  America,  they  are  divided  in  tlieir  beliefs  concerning  the 
])articular  locality  in  which  the  wild  tuber-bearing  species,  of  whicli 
it  is  a  descendant,  originally  occurred.  One  group  of  scientists 
claim  C!hili  as  the  original  home  of  the  potato,  while  another  group 
are  inclined  to  regard  Peru,  or  Peru  and  Bolivia,  as  the  region 
from  which  it  came.  Those  who  regard  Chili  as  its  source  appear 
to  be  in  the  majority ;  but,  to  the  writer,  the  evidence  seems  to  ])e 
in  favor  of  Peru,  or  possibly  of  the  wliole  Andean  section  of  South 
America,  stretching  from  the  northern  boundary  of  Ecuador  to  tlie 
southern  portion  of  Peru. 

Wight's^^  summation  of  the  evidence  both  for  and  against  its 
Chilean  origin  is  a  comprehensive  review  of  the  more  important 
literature  on  the  subject.  His  conclusions,  based  on  the  literature, 
a  critical  examination  of  material  in  American  and  Euro])ean  her- 
barias,  and  a  six  months'  exploration  trip  througli  Chili,  Peru, 
Bolivia  and  Ecuador,  (made  for  the  express  purpose  of  securing 
first-hand  information  concerning  the  existence  of  the  wild  form 
Solamiin  tiiberosunt,  L. ),  are  as  follows: 

"Every  reported  occurrence  of  wild  >S^.  tuberosum  that  I  have  been 
able  to  trace  to  a  specimen,  either  living  or  preserved  in  the  herbarium, 
has  proved  to  be  a  different  species.  In  fact,  so  far  as  the  herbarium 
material  is  concerned,  I  have  not  found  in  any  of  the  principal  European 
collections,  a  single  specimen  of  Holanum  tuberosum  collected  in  an 
undoubtedly  wild  state.  After  a  century  and  a  half  of  intermittent  collect- 
ing, there  is  no  botanical  evidence  that  the  species  is  now  growing  in  its 
original  indigenous  condition  anywhere.  So  far  as  the  number  and 
relationship  of  the  species  referred  to  the  section  tuberarium  are  con- 
cerned, the  evidence  is  in  favor  of  the  central  Andean  region." 

The  central  Andean  region  referred  to  comprises  northern 
Chili,  Peru,  Bolivia  and  Ecuador. 

Early  History. — The  first  mention  of  the  potato  in  literature 

is  that  found  in  Cieca's  "Chronicles  of  Peru"  published  in  Seville, 

Spain,  in  1553,     Cieca  was  a  young  Spanish  adventurer  who,  at 

the  early  age  of  fourteen,  sailed  with  an  expedition  from  Spain 

24  369 


370  ORIGIN  AND  EARLY  HISTORY 

to  Cartagena,  where  he  landed  in  January,  1833.  In  1838  he 
joined  an  expeditionary  force  that  crossed  the  mountains  and 
advanced  up  the  valley  of  the  Cauca.  In  1541  he  began  to  keep  a 
journal  wdiicli  he  continued  througliout  his  soldier's  career,  which 
took  him  southward  as  far  as  the  mines  of  Potosi  in  southern  Peru. 
Among  the  many  interesting  data  recorded  by  Cieca  in  his  journal 
were  those  pertaining  to  the  agricultural  regions,  through  which 
he  and  his  soldier  companions  fought  their  way  southward.  In 
Markham's"  English  translation  of  Cieca's  Chronicles,  the  potato 
is  alluded  to  seven  different  times  in  connection  with  different 
localities  through  which  he  passed. 

On  page  117  he  says:  "In  the  Provinces  of  Chapanchita,  Bomba  and 
Popayan.  .  .  .they  gather  great  quantities  of  potatoes."  On  page  121:  "The 
districts  of  Pasto  yield  but  little  maize.  .  .  .The  country  yields  much  barley, 
potatoes,  etc."  Page  131:  "In  all  these  villages  (Pasto,  Funes,  Gualmatan 
and  Ipiales),  they  grow  many  potatoes."  Page  143:  "Of  provision  besides 
maize,  there  are  two  other  products  which  form  the  principal  food  of 
these  Indians.  One  is  called  potato."  Page  174:  "In  the  Province  of 
Santiago  de  Puerto  Vie  jo  the  land  is  fertile,  yielding  an  abundance  of  maize, 
yucas,  aji,  potatoes  and  many  other  roots."  Page  234,  in  speaking  of  the 
crops  grown  in  the  fertile  coast  valleys,  Cieca  says:  "They  also  raise  sweet 
potatoes.  ..  .besides  potatoes,  beans  and  other  vegetables."  Pages  360-3G1, 
in  speaking  of  the  Callao  region,  he  says  of  the  inhabitants:  "Their 
principal  food  is  potatoes  which  are  like  earth  nuts.... They  dry  these 
potatoes  in  the  sun  and  keep  them  from  one  harvest  to  the  next.  After  they 
are  dried  tliey  call  these  potatoes  chufius,  and  they  are  highly  esteemed  and 
valued  among  them.  They  have  no  water  in  channels  for  irrigating  the 
fields,  as  in  many  other  parts  of  this  kingdom,  so  that,  if  the  natural  supply 
of  water  required  for  the  crop  fails,  they  would  suffer  from  famine  and  want 
if  they  had  not  this  store  of  dried  potatoes.  ]\Iany  Spaniards  have  enriched 
themselves  and  returned  prosperous  to  Spain,  1)y  merely  taking  these  chunus 
to  sell  at  the  mines  of  Potosi."  Cieca  describes  the  climate  of  the  Callao 
region  as  being  "so  cold  that  there  is  no  maize,  nor  any  kind  of  tree;  and  the 
land  is  too  sterile  to  yield  any  of  the  fruits  which  grow  in  other  parts." 

From  the  above  mention  of  the  potato  it  is  quite  evident  that 
it  was  a  common  article  of  food,  and  rather  generally  cultivated 
throughout  a  considerable  portion  of  the  region  transversed  by 
Cieca;  or  from  the  southern  portion  of  what  is  now  known  as 
Colombia,  to  the  region  of  Lake  Titicaca  or  beyond.  That  Cieca 
and  later  writers  recognized  that  the  potato,  or  "papas"  as  it  was 
universally  called  ])y  the  Indians,  had  long  been  under  cultivation 
in  that  region  is  quite  evident  from  their  writings.  It  is  not. 
strange,  therefore,  that  after  a  lapse  of  nearly  four  centuries  the 
evidences  of  its  origin  should  be  so  obscured  as  to  make  it  impossible 
for  any  person,  no  matter  liow  well  versed  in  the  origin  of  our 


INTRODUCTION  INTO  EUROPE  371 

cultivated  i:)laiits  he  may  be,  to  determine  definitely  what  the 
original  wild  form  may  have  been.  There  is  no  certainty  that  the 
plant,  to  which  the  name  Solanum  {uherosum,  L.  was  given,  was 
a  pure  wild  species.  The  reason  for  making  such  a  statement  is 
due  to  the  fact  that  the  plants  originally  studied  and  described  by 
both  Bauhin-  and  Clusius^  did  not  represent  a  pure  wild  species 
because,  according  to  both  of  these  botanists,  there  were  both  purple 
and  white  flowering  plants  among  the  seedlings  grown  from  them. 
This  is  directly  opposed  to  the  behavior  of  seedlings  grown  from 
any  of  the  wild  species  studied  in  the  past  fifteen  years.  In  not 
a  single  instance  has  it  been  found  that  such  seedlings  bore  either 
flowers  or  tubers  that  were  sensibly  different,  either  in  color  or  in 
form,  from  that  of  the  parental  plant.  These  observations  were 
made  on  the  following  species  of  Solanums:  cardiopliyllum,  dcmis- 
sum,  verrucosum,  utile,  polyademium  and  several  unidentified  ones 
from  South  America.  While  the  above  observation  does  not  neces- 
sarily prove  the  statement  made,  as  to  the  unlikelihood  of  the 
original  forms  studied  being  simon-pure  with  respect  to  certain 
unit  characters,  as,  for  example,  color  of  flowers  and  tubers,  it  does 
afford  conclusive  evidence  that  at  some  time  during  the  centuries 
preceding  those  in  which  the  Spaniards  found  the  potato  occupying 
an  important  place  as  an  article  of  food  in  the  Andean  region  of 
South  America,  two  or  more  species  must  have  hybridized ;  or  else 
we  must  accept  the  De  Vriesian  theory,  and  assume  that  mutants 
appeared  in  the  original  wild  species.  It  is  known  that,  at  the 
time  of  the  conquest  of  Peru,  more  than  one  variety  of  potato  was 
l)eing  grown  by  the  natives ;  and  that  then,  as  in  many  sections  of 
South  America  today,  the  potato  was  very  largely  reproduced  from 
true  seed,  rather  than  from  the  tubers.  It  is  the  exception  rather 
than  the  rule  today,  to  find  the  Indian  in  the  Andean  region 
growing  but  one  variety  in  his  potato  plot;  the  chances  are  strongly 
in  favor  of  his  having  a  dozen  or  more  different  varieties  (seedlings) 
intermingled  with  one  another. 

Introduction  into  Europe. — Its  introduction  into  Euroi)e  is 
supposed  to  have  occurred  shortly  after  the  Spanish  conquest  of 
Peru,  or  about  the  middle  of  the  sixteenth  century.  That  it  may 
have  been  carried  to  Europe  at  a  somewhat  earlier  date  is,  of  course, 
possible,  but  hardly  probable,  since  it  would  have  attracted  the 
notice  of  some  of  the  European  botanists  of  that  period.  It  is 
thought  to  have  been  carried  into  Italy  from  Spain,  and  from  Italy 
into  central  Europe. 


372  ORIGIN  x\xND  EARLY  HISTORY 

In  the  meantime,  the  potato  is  supposed  to  have  found  its  way 
into  the  Old  World  from  another  and  entirely  distinct  source,  if 
we  are  to  believe  the  commonly  accej)ted  notion  that,  in  1586,  it 
Avas  brought  to  England  in  one  of  Sir  Walter  Raleigh's  ships,  on  its 
return  from  the  colony  which  Sir  Walter  established  in  Virginia 
in  1584.  Upon  this  introduction,  or  theory  of  it,  Wight  (I.e.  p. 
39)  says: 

"The  idea  that  the  potato  Avas  introduced  from  Vir^fiiiia  into  Eujflaiid.  is. 
however,  so  prevalent  in  literature  that  it  should  have  some  consideration, 
even  thou<;h  the  claim  is  not  made  that  the  potato  was  native  to  Vir<>inia. 
Few,  in  fact,  have  believed  that  it  was  cultivated  by  the  Indians  previous 
to  the  era  of  European  exploration  and  settlement;  and  no  evidence  has 
ever  been  brought  forward,  so  far  as  I  am  aware,  in  support  of  such  a 
contention.  The  conclusion  in  regard  to  its  introduction  from  Virginia 
rests  solely  on  the  assumption  that  the  root  (called  by  the  Indian  Openauk) , 
described  by  Thomas  Ilariot  in  A  irief  and  true  report  of  the  new  found 
land  of  Virginia,  first  printed  in  London  in  158S,  is  the  potato;  and  is  also 
the  plant  described  by  Gerard  in  his  IlerbaU,  issued  in  1598.  Hariot  says: 
'These  roots  are  found  in  moist  and  marshy  grounds,  growing  many  together 
i!i  ropes  as  though  they  were  fastened  to  a  string.'  He  states  that  they 
gi'ew  naturally  or  wild,  which  would  be  improbable  if  they  were  potatoes 
introduced  after  the  discovery.  The  description  also  applies  better  to 
Apios  tuberosa,  the  ground  nut,  than  it  does  to  the  potato.  Furthermore, 
the  Indians  would  scarcely  have  had  a  distinctive  name  for  a  plant  so 
recently  introduced. 

"We  may  assume,  from  the  evidence  at  hand  as  to  the  improbability 
of  the  potato  being  known,  and  still  less  cultivated  in  Virginia  at  that 
time,  that  if  Raleigh's  vessels  in  charge  of  Sir  Francis  Drake  did  bring 
the  potato  to  England  on  the  date  mentioned,  they  must  have  secured  it 
from  some  South  American  trading  vessel,  or  at  a  point  other 
than  Virginia." 

The  first  published  description  ol'  tlie  potato  found  is  by 
Bauhin.-  While  it  was  based  on  rather  scanty  material,  it  is 
sufficiently  comprehensive  and  accurate  as  to  leave  no  doubt  in  the 
reader's  mind  as  to  its  being  the  potato.  In  describing  the  plant 
Bauhin  says : 

"The  stem  is  in  the  form  of  a  stalk  about  one  and  one-half  to  two  feet 

in   length;    fruit   in   the  sliape  of  a   golden   apple,   nearly    round stem 

green,   somewhat   branched,   nevertheless   it   sometimes   reaches   the   height 

of  a  man Leaves  about  the   length   of  the  hand,   rough   on   the  under 

side  with  pale  hair.  Much  divided  into  si.\,  eight  or  more  or  less  parts; 
like  single  leaves,  to  the  number  of  which  an  odd  one  is  always  added; 
round  to  oblong,  simple,  arranged  opposite  and  there  are  usually  two, 
six  or  more  small  leaves  interspersed  along  the  leaf  stalk. 

"The  branches  are  usually  divided  into  two  stalks,  each  of  which  bears 
many  flowers,  some  closed  and  three  or  four  open,  ranging  from  blue  to 
purplish,  spreading  out  into  five  points  which  somewhat  greenish-yellow 
lines  traverse  and  divide;  in  the  centre  there  are  usually  bunched  four 
reddish  stamens,  as  in  Malum  insanuni. 


INTRODUCTION  INTO  EUROPE 


373 


"The  flowers  are  succeeded  by  single  round  fruit?,  hanging  on  long 
stems,  like  a  cluster,  as  in  Holanum  vulgare,  but  far  larger;  for  some  of 
tliem  equal  a  nut  (probably  a  walnut)  in  size;  some  of  them  indeed  grow 
no  larger  than  a  filbert,  all  nevertheless  striped  with  equal  lines,  like 
the  Malum  aureum,  which  range  from  green  to  blackish  and,  when  mature, 


Fig.  201.— Bauhin  in  Prodrumus  Theniri  Bulanici,  1020. 

to  a  dark  red  (probably  a  dark  purplish-black).  In  these  the  seed  is  small, 
flat  and  round,  somewhat  swarthy. 

"The  root  is  round,  but  not  circular,  of  a  swarthy  or  dark  red  color; 
it  is  taken  up  from  the  earth  in  the  winter  time,  and  is  returned  to  the 
earth  in  the  spring. 

"At  the  base  of  the  stem,  at  the  head  of  the  main  root,  long  fibrous 
roots  are  spread  out,  on  some  of  which  small,  round  roots  are  borne  (tul)ers). 

"We  name  this  Holnnum  because  of  a  certain  form  of  its  leaves  and 
of  the  fruit,  which  is  like  Malum  aureum;  then,  of  the  flowers,  which  are 
like  Malum  insanum ;  then,  of  its  seed,  which  corresponds  to  the  Solani; 
and,  finally,  on  account  of  the  unpleasant  odor  of  it,  common  to  the  Solani." 

In  giving  his  source  of  information  Bauhin  says : 

"The  seed  was  sent  under  the  name  of  pappas  of  the  Spaniards,  and 
originally  of  the  Indians,  which  grew  easily  in  our  garden  almost  like 
a  leafy  shrub,  as  in  the  garden  of  Dr.  Martinius  Chmielecius,  who  had  one 
with  a  white  blossom.     On  account  of  our   long-standing  friendship,   Dr. 


374 


ORIGIN  AND  EARLY  HISTORY 


Laurentius  Scholtzius,  a  physician,  sent  me  a  drawing  of  a  plant  that 
he  had  grown  in  his  garden,  sketched  in  colors,  but  without  fruit,  and  the 
root  appendages."  *      (Fig.  201). 

In  this  publication  Bauhin  names  the  potato  Solanu7n  tuber- 
osum, but  in  Frodromus  Theatri  Botanici,  published  in  1620,  he 
changes  the  name  to  S.  tuberosum  esculentum. 

According  to  Mitchell/  Gerard  in  his  1596  catalogue  applied 
the  name  of  "Papas  orbiculatus"  to  the  potato.     He  evidently 


Fig.  202. — Rpproduction  from  Gerard's  Herball,  1697. 

changed  his  mind  when  he  published  his  Ilerball  in  1597  because, 

as  will  be  seen  from  the  reproduction   (Fig.  202),  he  renamed  it 

Batata  virginiana  sine  Virqinanorum  et  Papus. — Potatoes  of  Vir- 

•  Translated   from    the    Latin   by    Mrs.   Grace   Graham   Brannin. 


INTRODUCTION  INTO  EUROPE  375 

ginia.  In  his  1599  catalogue  he  again  refers  to  it  as  Papas  orbicu- 
latus.  Wight  (I.e.  p.  40)  in  commenting  on  these  inconsisten- 
cies says : 

"It  is  curious,  if  Gerard  had  the  plant  described  by  Hariot,  that  he  did 
not  use  his  name  ( Openauk )  instead  of  a  word  which  is  not  known  to  liave 
occurred  in  the  Indian  language  within  the  present  border  of  the  United 
States  or  Canada.  The  question  of  how  Gerard  came  by  the  word  'papas' 
may  be  settled  with  reasonable  certainty,  for  he  says :  'It  groweth  naturally 
in  America  where  it  was  first  discovered,  as  reporteth  C.  Clusius.  .  .  .It 
is  doubtful  if  Clusius  would  have  reported  anything  concerning  the  potato 
before  he  had  received  tubers,  which  was  in  1588,  two  years  after  Harlot's 
return  from  America;  yet  Gerard  says:  'since  which  time  (referring  to 
the  statement  of  Clusius )  he  had  received  roots  from  Virginia,'  and  this 
would  indicate  that  he  must  have  received  roots  from  some  other  voyage. 
The  figure  in  the  Herhall  is  in  two  parts,  and  it  may  be  doubted  if  the 
tubers  figured  are  potatoes,  at  least  this  part  of  the  figure,  for  some  reason, 
is  changed  in  Johnson's  edition  of  the  Herhall  in  1636." 

If  judged  literally,  one  might  well  question  whether  Gerard's 
illustration  of  the  root  and  tuher  development  of  the  potato  was 
really  made  from  the  potato.  If,  on  the  other  hand,  we  regard 
it  as  a  purely  diagrammatic  drawing,  we  may  accept  it  for  what 
it  is  intended  to  convey,  rather  than  what  it  actually  does  convey 
to  the  mind.  The  stem,  leaves,  flowers  and  fruits  are  sufficiently 
accurate  as  to  leave  no  question  in  one's  mind  as  to  its  identity. 

In  1601,  Clusius  j^ublished  a  description  of  the  potato  in  his 
Rariorum  Plantarum  Hisioria,  Chap.  LII,  p.  LXXIX,  in  which 
he  calls  it  Papas  Peruanorum.  Clusius  begins  his  description 
by  saying: 

"There  is  an  edible  root  of  a  new  plant,  which  but  a  few  years  ago 

Avas  not  known  in  Europe It  springs  at  first  from  a  bulb,  which,  with 

us,  starts  into  growth  about  April,  not  later;  within  a  few  days  after 
planting  it  puts  forth  leaves  of  a  dark  purplish  color,  hairy,  which, 
presently  unfolding,  show  a  green  color;  5,  7  or  more  leaflets  on  the  same 
stem,  not  very  different  from  the  radish,  always  of  an  odd  number,  some 
smaller  leaves  being  interspersed,  and  the  odd  one  always  occupying  the 
extreme  tip  of  the  petiole.  The  stem  is  of  the  thickness  of  the  thumb, 
angular,  and  covered  with  down.  From  the  axils  of  the  petioles  coarse 
stalks  appear,  angular  pedicels,  bearing  10  to  12  or  more  flo\\'ers  aI)oiit 
an  inch  or  more  across,  angular,  consisting  of  one  piece,  but  so  folded  that 
there  appear  to  be  five  separate  leaves,  of  a  whitish-purple  on  the  outside, 
inside  purplish,  with  five  green  rays  appearing  from  the  centre  like  a 
star,  with  yellow  stamens  gathered  together  in  the  centre,  and  a  prominent 
greenish  style.  After  the  flowers,  which  bear  an  odor  resembling  the  odor 
of  the  flowers  of  the  linden,  roimdish  apples  appear,  not  much  different 
from  the  fruit  of  the  mandrake,  only  smaller,  green  at  first,  white  at 
maturity;  full  of  juicy  pulp  which  contain  many  flat  seeds  scarcely  larger 
than  the  seeds  of  the  fig." 

In  describing  the  tuber  development  he  says: 


376 


ORIGIN  AND  EARLY  HISTORY 


->     V 


Fig.  203. — Reproduction    of  drawing  of  potato  stem   sent  to  Clusius  by  Philip    de 
Sivey  in  15S8. 

"When,  in  the  month  of  November,  the  plant  is  dug  after  the  first 

frosts,   there  are  discovered   tubers   of   various   sizes.      These   are   uneven, 

recognized  by  certain  marks  whence,  the  following  year,  shoots  will  start 

forth.     I  remember,  also,  that  there  were  collected  more  than  50  tubers 


INTRODUCTION  INTO  EUROPE 


377 


from  one  single  plant,  some  so  large  that  they  weigh  an  ounce  or  even  two, 
the  outside  skin  reddish  or  approaching  a  purple  color,  some  small,  as 
though  not  yet  mature;  they  have  a  whitish  skin  which  is  very  tender 
in  all  the  tubers,  but  the  flesh  itself  is  firm  and  white. 

"From  the  tubers  alone  therefore,  we  must  expect  the  preservation 
of  the  genus,  and  from  the  seed,  the  daughter  plants  of  which,  in  the 
same  year,  bear  blossoms,  but  of  a  diff'erent  color  from  the  mother  plant. 
So  I  have  learned  from  others,  though  I  have  never  tried  the  experiment 


Fig.  204. — Reproduction  of  Clusius  dra\ 


from  the  living  potato  plant,  1601. 


myself.  True  it  is  that  my  friend  Joannes  Hogeladius  described  plants 
to  me  produced  from  seed  which  I  sent  him,  Avhich  produced  white  blossoms 
altogether.  I  received  the  first  authentic  information  about  this  plant 
from  Phillipus  de  Sivcy,  Dn.  de  Walhain  and  Prefect  of  the  City  of  Mons 
in  Hannonia.  of  the  Belgians,  who  sent  two  tubers  of  it,  with  its  fruit,  to 
me  at  Vienna,  Austria,  at  the  beginning  of  the  year  1-187.  and  in  the 
following  ,year,  a  drawing  of  a  branch  with  a  flower,  ( Fig.  203 ) .  He  wrote 
that  he  had  received  it  the  preceding  year  from  a  certain  employee  of 
the  Pontifical  Legation  in  Belgium.  Later  Jacobus  Garerus,  Jr.,  sent  me 
a  Frankfort  drawing  of  a  whole  stalk,  Avith  roots.  Indeed,  I  have  much 
desired  to  exhibit  the  whole  plant  here,  but  I  have  taken  pains  to  portray 
it  in  two  drawings  from  the  living  plant — one  representing  flowers  and 
fruit,  the  other  roots  and  tubers  clinging  to  their  own  fibres,   (Fig.  204). 


378  ORIGIN  AND  EARLY  HISTORY 

"The  Italians  do  not  know  where  they  were  first  produced.  Certain 
it  is,  however,  that  they  were  obtained  either  from  Spain  or  from  America. 
It  is  a  great  wonder  to  me  that,  when  it  was  so  common  and  frequent 
in  Italian  settlements  (so  they  say),  that  they  feast  upon  these  tubers, 
cooked  with  flesh  of  mutton,  in  the  same  manner  as  upon  turnip  and 
carrots,  they  give  themselves  the  advantage  of  such  nourishment,  and 
allow  the  news  of  the  plant  to  reach  us  in  such  an  off-hand  way.  Now, 
indeed,  in  many  gardens  of  Germany  it  is  quite  common  because  it  is 
very  fruitful."  ** 

Authorities  Differ. — It  is  apparent  to  the  reader  that  there  are 
some  inconsistencies  in  the  description  of  the  potato  by  both 
Bauhin  and  Clusius.  Take  for  example  Bauhin's  description  of 
the  fruits,  which  he  says  are  dark  red  when  mature.  In  many 
of  the  varieties  from  South  America  which  have  come  under  our 
observation,  the  mature  fruits  are  a  dark  purplish-black  or  dark 
bluish-green  black,  whereas  in  all  varieties  that  are  classified  under 
groups  1  to  12  in  Chapter  XII  they  are  a  light  lemon-yellow  color 
when  mature. 

In  view  of  this  fact,  we  may  accept  Bauhin's  description  of  the 
color  as  not  entirely  inaccurate.  It  requires  some  imagination 
on  the  other  hand  to  accept  Clusius's  statement  that  the  odor  of 
the  potato  flower  resembles  that  of  the  linden.  His  description 
of  the  color  of  the  mature  fruits  would  indicate  that  the  variety  he 
had  was  different  from  that  of  Bauhin's.  The  accuracy  of  obser- 
vation of  Clusius  is  well  indicated  in  his  description  of  the  color  of 
the  tubers  in  which  he  says  "some  small,  as  though  not  yet  mature, 
they  have  a  whitish  skin."  This  observation  has  been  repeatedly 
verified  in  studying  a  number  of  tuber-bearing  species  of  Solatium 
from  Mexico.  The  immature  tubers  very  frequently  do  not  show 
color,  whereas  when  they  mature,  several  species  have  always 
developed  a  purplish  color. 

Development  of  Potato  Culture  in  Europe. — While  we  have 
little  definite  knowledge  as  to  how  extensively  the  potato  was  culti- 
vated prior  to  the  seventeenth  century,  we  can  safely  assume  that 
it  had  not  yet  emerged  from  the  curiosity  or  novelty  stage  in  its 
development  as  a  staple  food  plant,  although  Clusius  (I.e.  p.  1601) 
says  that  it  is  reported  to  be  more  or  less  commonly  grown  in 
Italy,  and  further  remarks  that,  because  of  its  fruitfulness,  it  is 
quite  commonly  grown  in  many  gardens  of  Germany.  Despite 
these  statements  of  Clusius,  the  fact  remains  that  the  potato  was 
•♦Translated   from   the  Latin  by  Mrs.   Grace   Graham   Brannin. 


POTATO  DEVELOPMENT  IN  PRUSSIA  379 

little  grown  in  Europe  before  the  latter  part  of  the  seventeenth 
century,  and,  in  fact,  did  not  become  of  great  commercial  impor- 
tance until  the  latter  half  of  the  eighteenth  century. 
Development  in  Great  Britain. — Phillips^'^  says : 

"The  potato  first  became  an  object  of  national  importance  in  1662-3 
as  appears  by  the  record  of  a  meeting  of  the  Royal  Society  held  March 
18  in  that  year;  when  a  letter  was  read.  ..  .recommending  the  planting 
of  potatoes  in  all  parts  of  the  kingdom  to  prevent  famine Notwith- 
standing, it  Was  not  till  within  the  last  twenty  years  (1802)  that  they 
were  used  as  a  substitute  for  corn  bread  (wheat  bread)  in  England, 
when  the  apprehension  of  a  scarcity  induced  all  prudent  families  to  adopt 
the  use  of  potatoes  at  their  dinner  tables,  in  lieu  of  bread  or  puddings." 

Miller^  in  1731  mentions  two  varieties  or  sorts,  the  red  and  the 
white  which,  he  says,  were  both  indifferently  cultivated  in  England 
at  that  time.  Krichauff^  says  that  up  to  1784  potatoes  were  chiefly 
grown  in  the  gardens  of  peers  and  rich  men;  and  that  in  179G 
Essex  County,  England,  grew  about  1,700  acres  for  the  London 
market.  In  Scotland,  he  says,  that  prior  to  1760  they  were  mostly 
grown  in  gardens ;  after  that  date  they  were  more  generally  grown. 
Loudon"  makes  a  very  similar  statement  in  1830,  in  which  he  says 
that  the  cultivation  of  potatoes,  even  in  gardens,  was  little  under- 
stood prior  to  1740;  and  that  it  was  about  twenty  years  later  before 
they  were  much  grown  as  a  field  crop.  He  further  mentions  the 
fact  that  the  famous  nursery  firm  of  London  and  Wise  did  not 
consider  the  potato  worthy  of  notice  in  their  Complete  Gardener, 
published  in  1719,  He  also  observes  that,  in  addition  to  the  acre- 
age grown  in  Essex  County  in  1796,  many  fields  could  be  noted 
in  other  counties  bordering  on  the  capital,  (London);  that  many 
shiploads  were  annually  imported  from  a  distance;  and  that  in 
1830,  the  potato  was  more  or  less  an  object  of  field  culture  in  every 
county  in  England. 

The  development  of  potato  culture  in  Ireland  was  contempo- 
raneous with  that  of  England ;  in  fact,  the  potato,  on  account  of  its 
yield  per  acre  and  relative  cheapness,  became  a  vital  source  of  food 
supply  to  the  inhabitants  of  Ireland  at  a  much  earlier  date  than  in 
England,  Indeed,  if  we  may  judge  acreage  as  a  criterion  of  the 
importance  of  a  crop,  Ireland's  preference  for  the  potato  is  well 
indicated,  as  in  1917  she  grew  709,000  acres  of  potatoes  as  against 
England's  473,000  and  Scotland's  148,000. 

Potato  Development  in  Prussia. — The  following  incident, 
recorded  by  Krichauff  {I.e.),  casts  a  rather  interesting  sidelight  on 


380  ORIGIN  AND  EARLY  HISTORY 

the  attitude  of  the  Prussian  j)easants  and  the  people  in  general 
toward  the  use  of  the  potato  as  a  food  plant.  The  incident  cited 
is  as  follows: 

"Frederick  the  Great  of  Prussia  was  more  successful  than  his  father 
ill  introducing  the  cultivation  of  potatoes  into  Pomerania  and  elsewhere; 
hut  he  liad  recourse  to  his  soldiery,  who  had  to  force  the  farmers  to  plant 
them.  If  it  had  not  been  for  the  jjreat  famine  in  Germany  in  1771-72,  the 
f^reat  benefit  of  the  cultivation  of  potatoes  would  not  have  been  so  gen- 
erally  acknowledged." 

Potato  Development  in  France. — Potato  development  in 
France  was  somewhat  slower  than  in  Great  Britain,  Germany, 
Austria  or  the  adjoining  countries.     Krichauff  (I.e.)  says: 

"In  1771  a  high  prize  was  offered  by  the  Academy  of  Besancon  for 
the  discovery  of  a  new  food  which  would  fill  the  place  of  cereals  in  case 
of  a  famine.  Parmentier  showed  his  potatoes,  and  Louis  XVI  gave  him 
50  morgen  of  land  (a  morgen  equals  2.11  acres)  to  plant  them  on.  When 
showing  the  first  flowers  of  his  potatoes  the  king  used  them  as  a  buttonhole 
bouquet;  Queen  Marie  Antoinette  had  them  in  the  evening  in  her  hair, 
and  at  once  princes,  dukes  and  high  functionaries  M-ent  to  Parmentier  to 
obtain  such  flowers.  All  Paris  talked  of  nothing  but  potatoes  and  the 
cultivator  of  them.  The  king  said:  'P" ranee  will  thank  you  some  time 
hence,  because  you  have  found  bread  for  the  poor.'  And  France  has  not 
forgotten  Parmentier,  for  I  saw  for  myself  in  1882,  potatoes  growing  on 
his  grave  in  the  grand  cemetery  of  Paris,  the  PCre  Lachaise,  and  I  was 
assured  that  they  were  planted  there  every  year  so  that  his  services  might 
never  be  forgotten  by  Frenchmen  " 

Vilmorin"  admits  that  the  culture  of  the  potato  was  well 
established  in  Germany  when  it  was  still  in  an  embryonic  stage  in 
France,  except  in  the  Ardennes  region.     He  further  says : 

"During  the  Avhole  of  the  seventeenth  century,  and  in  all  probability  the 
greater  part  of  the  eighteenth,  the  potato  of  Clusius  seems  to  have  been  solely 
cultivated,  and  did  not  give  but  a  single  variety  with  white  flowers.  But 
in  1777  Engel  catalogued  40  varieties.  Parmentier  in  1786  counted  11  and 
in  1809,  12,  saying,  elsewhere,  that  other  authors  cited  more  than  (iO 
varieties.  The  Society  National  d'Agriculture  de  France  (then  Imperial) 
gathered  together  in  1814  and  1815  a  collection  of  115  to  120  varieties, 
which  was  confided  to  my  great-great-grandfather  and  which  was  the 
beginning  of  a  collection  that  I  still  possess." 

Potato  Development  in  Sweden. — Tn  an  unsigned  article 
appearing  in  the  page  devoted  to  "short  notes  from  papers"  of  The, 
Gentleman's  Mag.  vol.  34,  p.  579,  1764,  the  following  mention  is 
made  of  potato  culture  in  Sweden : 

"It  seems  strange  to  us,  but  it  seems  it  is  a  fact,  that  the  Swedes 
have  but  just  discovered  the  culture  of  potatoes,  notwithstanding  the 
indefatigable  industry  of  the  great  Linnaeus.  A  royal  edict,  however,  is 
now  issued  to  encourage  their  cultivation." 


POTATO  DEVELOPMENT  IN  AMERICA  381 

Potato  Development  in  India. — The  following  remarks  by 
Johnson*  are  illuminating  in  that  they  reveal  very  much  the  same 
conditions  as  in  Euroi)e : 

"At  the  horticultural  show  in  Calcutta  during  1842,  I  saw  potatoes 
exhibited  which  would  not  have  shamed  the  potato  growers  of  Lancashire, 
(England),  if  mistaken  for  their  produce.  These  were  grown  in  the 
immediate  vicinity  of  the  city,  but  in  the  hills  of  Chirra  Pongie,  though 
not  far  distant,  the  potatoes  are  grown  still  finer.  They  were  an  object 
of  cultivation  there  during  the  Governor-Generalship  of  Warren  Hastings 
(1772-1785),  and  alluding  to  that  period  a  writer  says:  "Three  score  years 
ago,  a  basket  of  potatoes,  weighing  about  a  dozen  pounds,  was  occasionally 
sent,  as  opportunity  offered,  by  Warren  Hastings  to  the  Governor  of 
■Bombay,  and  was  considered  an  acceptable  present.  On  reception,  the 
members  of  the  council  were  invited  to  dine  with  the  Governor  to  partake 
of  the  rare  vegetable.'  " 

Potato  Development  in  America. — If  we  turn  to  America, 
we  find  that  the  ])otato  was  i)robal)ly  unknown  to  American  agri- 
I'ulture  in  either  the  sixteenth  or  seventeenth  century  and  that  it 
was  not  until  the  early  part  of  the  eighteenth  century  that  they 
were  first  introduced  into  this  country.  Watson/-  in  his  Annals 
of  Philadelphid,  published  the  following  paragraph  regarding 
potatoes : 

"This  excellent  vegetable  was  very  slow  of  reception  among  us.  It 
was  first  introduced  from  Ireland  in  1719,  by  a  colony  of  Presbyterian 
Irish,  settled  at  Londonderry,  in  New  Hampshire.  They  were  so  slow  in 
its  use  in  New  England  that,  as  late  as  1740,  it  was  still  a  practice  with 
masters  to  stipulate  with  some  apprentices  that  they  should  not  be  obliged 
to  use  them.  The  prejudice  was  pretty  general  against  them  that  thev 
would  sliorten  mens'  lives  and  make  them  unhealthy,  and  it  was  only 
wlien  some  people  of  the  better  sort  chose  to  eat  them  as  a  palatable  dish 
that  the  mass   of   the   people   were   supposed   to   give   them   countenance." 


On  page  486  of  the  same  volume  Watson  further 


says : 


"As  late  as  my  mother's  childhood  potatoes  were  then  in  much  less 
esteem  than  now.  The  earliest  potatoes,  like  the  originals  now  discovered 
from  South  America,  were  very  small,  compared  with  the  improved  stock. 
They  were  small,  bright-yellow  ones,  called  kidney  potatoes,  and  probably 
about  seventy-tive  years  ago,  they  then  first  introduced  a  larger  kind, 
more  like  the  present  in  use,  which  were  called  in  New  England  the  Bilboa! 
In  Pennsylvania  the  same  kinds  of  potatoes  were  called  Spanish  potatoes." 

Bailey-"  makes  the  following  statement: 

"Pro])ably  the  potato  was  served  as  an  exotic  rarity  at  a  Harvard 
installation  in  1707,  but  the  tuber  was  not  brought  into  cultivation  in 
New  England  till  the  arrival  of  the  Presbyterian  immigrants  from  Ireland 
in  1718."  He  further  states  that  "only  two  Varieties  were  listed  in  1771, 
yet  by  the  end  of  the  eighteenth  century  they  were  numerous." 


382  ORIGIN  AND  EARLY  HISTORY 

QUESTIONS  ON  THE  TEXT 

1.  What   is    the   common   belief   regarding   the   origin    of   our    cultivated 

potato? 

2.  When  and  where  was  the  potato  first  mentioned  in  literature? 

3.  Where  was  tlie  potato  usually  grown  in  those  days? 

4.  What  can  you  say  of  it  as  a  food  plant  at  that  time? 

5.  How  was  it  preserved  for  future  use  by  the  natives? 

6.  How  does  the  evidence  at  hand  justify  an  acceptance  of  the  common 

belief  that  the  present  cultivated  varieties  of  the  potato  are  the 
direct  descendants   of   the   wild   species   Solanum   tuberosum,   L.  ? 

7.  When  was  the  potato  first  introduced  into  Europe? 

8.  What    does    Wight    say    about    its    introduction    from    Virginia    into 

England  ? 
1).  In    what    publication    was     the    potato     first    described?     What    did' 
Bauhin  name  it? 

10.  What  are  the  inconsistencies  noted  in  Gerard's  description  of  the  potato 

in  his  Hcrball  in  1597  ? 

11.  When   and   where  did   Clusius   publish  his   description   of   the  potato? 

What  did  he  name  it? 

12.  What  does  he  say  about  the  tubers? 

13.  Did  the  potato  at  once  become  popular  in  Europe?     If  not,  give  reasons. 

14.  Give  brief  account  of  its  development  in  Great  Britain. 

15.  Why  did  the  potato  become  popular  in  Ireland  before  it  did  in  England 

or  on  the  Continent? 

16.  How  was  the  potato  popularized  in  Prussia? 

17.  How  did  potato  development  in  France  compare  with  that   in  Great 

Britain  and  other  European  countries? 

18.  What  does  Krichauff  say  about  Parmentier's  part  in  popularizing  the 

potato  in  France? 

19.  What  does  Vilmorin   say  about  the  lack  of  popularity  of  the  potato 

in  his  country? 

20.  Compare  the  early  culture  of  the  potato  in  Sweden  with  that  in  other 

European  countries. 

21.  What   about  potato  development   in    India? 

22.  When    was    the    potato    first    introduced    into    America,    and    where 

first  grown? 

EXERCISES  AND  QUESTIONS   SUGGESTED  BY   THE  TEXT 

1.  Collect    flowers    of    several    varieties    of    potatoes    in    different    stages. 

What  variation   in  color  do  you  find? 

2.  Compare  young  tubers  with  mature  ones  of  the  same  variety.     What 

variation  in  color  do  you  find? 

3.  In  harvesting  potatoes,  note  the  attachment  of  potatoes  to  their  stems. 

What   likeness  do  you   find,   if  any,   to   their   being   "attached   in 
chains"? 

References   Cited 

1.  Bailfa-,  L.  H.     1912.     Potato  history.     Cycl.  Agr.  2:   520,  1912. 

2.  Bauiiin,  Caspar.     1596.     Phytopinax.     1596:  301-302. 

3.  Clusius,  C.     1601.     Rariorum  plantarum :   79,  Chap.  LII,   1601. 

4.  Johnson,  G.   W.      1847.     The  potato,   its   culture,   uses   and  history. 

The  Gard.  Mo.  1:  19,  London,  1847. 


REFERENCES  CITED  383 

5.  Kbichauff,  T.  E.  H.  W.  1895-96.  The  tercentenary  of  the  introduc- 
tion of  the  potato  into  England.  Jour.  Roy.  Hort.  8oc.  19: 
225,  18!)5-9C. 

(J.  LouuoN,  J.  C.     1830.    Encycl.  of  Gardening,  2nd.  od:  624,  London,  1830. 

7.  Markiiam,  C.     1864.     The  travels  of  Pedro  di  Cieza  de  Leon.     First 

part  of  his  chronicles  of  Peru  (Transl.  of.)    Ilakhtyt.  Soc,  London, 
33:   1-438,  1864. 

8.  Miller,  P.     1731.    Gardeners'  and  Botanists'  Diet.     1 :  1731,  not  paged. 

9.  Mitchell,  W.  S.      1886.     The  origin  of  the  potato.     Gard.  Chron.  n. 

ser.  5,  19:  303,  1910. 

10.  Phillips,  H.     1822.    Histori/ of  Cultivated  Tegetahles.    2:  87,  London, 

ser.  25:  487,  553,  585,  1886. 

11.  ViLMORiN.   Ph.   de.      1910.      Pommes   de   terre.      J'ev.    Gen.   Aaron.,   n. 

1822. 

12.  Watson,  J.  F.     1844.    Annals  of  Philadelphia.     2:  420,  1844. 

13.  Wight,  W.   F.      1917.     Origin,  introduction   and  primitive   culture  of 

the  potato.     Proc.  Third  Atin.  Meeting  of  the  Pot.  Ass'n.  of  Am., 
Nineteen  Sixteen:  35-52,  1917. 


CHAPTER  XXI 
POTATO  BREEDING  AND  SELECTION 

To  the  uninitiated,  the  subject  of  plant  breeding  seems  to  be 
surrounded  with  much  mystery.  This  is  probably  largely  due  to 
the  fact  that  the  reproductive  organs  of  plants  and  the  functions 
performed  by  them  are  relatively  little  understood  by  the  average 
person,  but  when  once  familiar  with  these  processes,  plant  l^reeding 
is  no  more  mysterious  than  animal  breeding,  in  fact  the  same 
general  laws  of  reproduction  apply  to  both. 

Breeding  and  Selection  Defined. — Before  proceeding  further 
with  the  discussion  of  breeding  and  selection,  as  related  to  the 
potato,  it  seems  desirable  to  briefly  define  the  use  and  the  application 
of  these  two  terms  in  the  present  work.  Breeding,  as  here  em- 
ployed, refers  strictly  to  sexual  reproduction.  Selection  refers  to 
the  isolation  of  any  desirable  variation  in  a  variety  from  that  of 
the  normal,  and  its  ])erpetuation  by  asexual  ])ropa;gation. 

Limitations  of  Breeding  and  Selection. — Broadly  speaking, 
the  limitations  of  potato  breeding  are  those  found  within  the  con- 
fines of  the  tuber-bearing  species  of  Solanums,  but  for  the  most 
part  it  may  be  regarded  as  being  confined  to  the  varieties  occurring 
Avithin  the  species  to  which  the  potato  is  assumed  to  belong.  The 
breeder  has,  therefore,  within  his  power  the  possibility  of  crossing 
two  varieties,  each  of  which  may  have  certain  desirable  qualities 
not  possessed  by  the  other,  with  the  view  of  combining  them  in 
some  of  the  resulting  offs])ring. 

The  improvement  of  the  potato  by  selection  is  limited  to  the 
natural  variations  occurring  within  the  individual  variety  itself. 
As  not  all  such  variations  are  heritable,  one  cannot  always  be 
certain  that  the  mere  selection  of  a  variant  means  progress  until 
it  is  thoroughly  tested.  The  selectionist,  therefore,  has  a  much 
narrower  field  than  that  of  the  breeder. 

Nineteenth  Century  Potato-breeding  Achievements. — Lit- 
tle, if  any,  real  ])rogress  was  made  in  jiotato  Ijrcediiig  ])rior  to  1850, 
either  in  America  or  in  Europe.  From  this  period  on,  however, 
ra])id  strides  were  made  in  the  development  and  improvement  of 
commercial  varieties  of  potatoes.  During  this  period,  the  chief 
consideration  in  the  minds  of  American  potato  breeders,  aside  from 
384 


THE  WORK  OF  GOODRICH  385 

those  of  Goodrich,  seemed  to  be  that  of  attractive  appearance,  table 
quality  and  })roduetivenes,s.  European  breeders,  on  the  other 
hand,  paid  quite  as  much  attention  to  disease  resistance  and  starch 
content  as  to  the  other  factors  mentioned. 

American  Potato  Breeders  and  Their  Accomplishments. — 
To  attempt  an  enumeration  of  all  American  potato  breeders  wlio 
have  had  a  part  in  the  improvement  of  the  potato  during  the  last 
half  of  the  nineteenth  century  is  neither  feasible  nor  desirable. 
But,  in  order  to  intelligently  trace  the  progress  made,  from  the 
time  of  Goodrich  to  that  of  Carman  and  others,  the  following  list 
of  names  is  presented  as  worthy  of  mention :  Goodrich,  Bresee, 
Brownell,  Pringle,  Eand,  Gleason,  Heffron,  Burbank,  Alexander, 
Reese,  Coy,  Carman,  Craine,  Bovee,  Safford  and  Van  Ornam. 

The  Work  of  Goodrich. — The  severe  epidemic  of  late  blight 
that  swept  over  this  country  and  Europe  during  the  years  1843  to 
1847,  and  reached  its  climax  in  Europe  in  1845,  causing  a  wide- 
spread famine  in  Ireland,  led  the  Eev.  Chauncey  Goodrich  of 
Utica,  New  York,  to  conceive  the  idea  that  the  potato,  as  a  result 
of  long  continued  asexual  propagation,  had  become  so  weakened  in 
vigor  as  to  be  no  longer  able  to  successfully  resist  the  attack  of 
disease.  He  believed  that  it  could  only  be  rejuvenated  through 
sexual  reproduction,  and  began  to  make  his  plans  for  the  growing 
of  seedling  potatoes,  with  the  idea  of  developing  more  vigorous  and 
productive  varieties  that  would  be  able  to  very  largely  resist  disease. 
Through  the  kindness  of  the  American  consul  at  Panama,  Goodrich, 
in  1851,^-  received  a  small  quantity  of  South  American  potatoes 
for  breeding  purposes.  Among  this  lot  was  a  variety  which,  from 
its  rough,  pur])le  skin  and  its  supposed  place  of  origin,  he  descrip- 
tively named  the  Eough  Purple  Chili.  From  naturally  fertilized 
seed  balls  of  this  variety,  produced  in  1852,  he  grew  some  seedlings 
in  1853;  and  from  this  lot  one  was  selected  as  worthy  of  propa- 
gation. This  seedling  was  introduced  in  1857,  under  the  name  of 
Garnet  Chili.     In  speaking  of  his  work  Goodrich  says: 

"From  the  beginning  of  1849  to  the  close  of  1854  I  originated  about 
5,400  varieties ....  I  have  but  33  sorts  left,  many  of  which  I  shall  doul)tles3 
reject  in  a  year  or  two.  The  3,000  new  sorts,  originated  in  1855  and  1856, 
promise  better,  but  even  among  them  the  proportion  of  truly  valuable 
ones  will  in  the  end  doubtless  be  small." 

Goodrich's   statements  regarding  the   relatively  few   desirable 
seedlings  that  are  likely  to  be  obtained  by  the  plant  breeder  indicates 
a  careful  and  conscientious  rejection  of  all  inferior  plants,  and  a 
25 


386  POTATO  BREEDING  AND  SELECTION 

firm  resolve  not  to  offer  to  the  trade  any  unmeritorious  varieties. 
That  he  had  a  clear  notion  of  the  problem  before  him  is  evidenced 
by  his  summation  of  what  he  considered  were  the  important  traits 
which  should  be  included  in  a  valualjle  variety  of  potatoes.  These 
are  as  follows:  (1)  Good  shape;  (2)  white  flesh;  (3)  hardiness; 
(4)  freedom  of  growth;  (5)  resistance  of  dry  weather;  (6)  fine 
flavor;  (7)  early  maturity.  Not  only  does  he  mention  these  attri- 
butes of  a  good  variety  but  he  also  indulges  in  a  discussion  of 
varieties  having  the  right  shape  and  those  that  did  not.  He 
further  shows  his  familiarity  with  the  behavior  of  varieties,  by 
citing  those  possessing  what  he  terms  good  bases  from  which  to 
grow  a  large  proportion  of  seedlings  having  shapely  tubers.  For 
example,  he  mentions  the  Eough  Purple  Chili  as  a  bad  base  to  use 
for  shape,  but  a  good  one  for  color  of  flesh  and  hardiness. 

So  far  as  known,  Goodrich  did  not  do  any  artificial  crossing; 
all  of  his  seedlings  being  produced  from  naturally  fertilized  seed 
balls.  While  in  this  respect  he  failed  to  perform  the  highest 
type  of  plant  breeding,  his  work,  nevertheless,  impresses  one  as 
having  been  carefully  conducted.  The  varieties  that  he  originated 
were  the  Calico,  Cuzco,  Early  Goodrich,  Garnet  Chili  and  several 
others.  Of  these,  the  Garnet  Chili  is  still  being  groA\m  as  a  com- 
mercial variety  in  some  localities. 

The  importance  of  Goodrich's  work  lies  not  so  much  in  what 
he  himself  originated,  but  rather  in  the  varieties  produced  by 
others  from  his  Garnet  Chili  seedling.  In  a  remarkable  tribute 
to  Goodrich,  Henry  Ward  Beecher  says^ : 

"There  are  few  instances  on  record  of  zeal  so  interested,  chiefly  in 
two  respects.  First,  in  that  he  would  not  permit  himself  to  be  imposed 
upon  in  the  judgment  which  he  placed  upon  the  merits  of  his  seedlings; 
and,  secondly,  in  that  he  worked  out  his  benevolent  labors  to  the  end  of 
his  life,  without  turning  his  industry  to  his  own  profit.  He  was  so 
busy  with  his  experiments  that  he  had  no  time  to  make  money" 

He  was  a  prolific  writer,  and  something  like  130  articles  from 
his  pen  were  published  in  the  horticultural  and  agricultural  journals 
and  reports  of  that  period.  There  can  be  no  question  as  to  the  tre- 
mendous impetus  his  work  and  his  writings  imparted  to  those  who 
later  followed  in  his  footsteps. 

Work  of  Albert  Bresee. — The  next  important  contribution 
to  the  list  of  potato  varieties  in  America  was  the  Early  Rose.  This 
variety  was  originated  in  1861  by  Albert  Bresee,  of  Hubbardson, 
Vermont,  from  a  naturally  fertilized  seed  ball  of  Garnet   Chili, 


THE  WORK  OF  C.  G.  PRINGLE  387 

and  was  introduced  in  a  limited  way  in  1867.  The  Early  Rose 
may  be  regarded  as  the  first  really  promising  commercial  variety 
produced  in  America.  It  may  also  be  regarded  as  the  foundation 
stock,  from  which  emanated  many  of  our  present  day  varieties. 
Bresee  also  originated  King-of-the-Earlies,  Peerless  and  Prolific. 

The  work  of  C.  G.  Pringle  of  Charlotte,  Vermont,  will 
always  stand  forth  in  the  minds  of  American  potato  breeders  as 
representing  the  first  careful  effort  to  cross  potato  varieties,  with 
the  object  of  combining  in  the  resultant  offspring  certain  desirable 
characters  of  the  parent  plants.  Pringle  was  a  close  observer  of 
nature,  a  keen  student  and  a  good  botanist,  and  he  early  acquired 
such  skill  in  the  technic  of  crossing,  that  we  find  him  in  the  early 
seventies  contracting  with  a  leading  seedsman  of  New  York  City  to 
produce  hybridized  potato  seed  at  $1,000  per  pound.  Considerable 
seed  was  produced  at  this  price  and,  through  the  seedsman,  was 
widely  disseminated.  There  is  every  reason  to  believe  that  Priugle's 
hybridized  seed  produced  many  varieties  for  which  the  hybridizer 
never  received  the  credit.  His  varietal  contributions  were  the 
Alpha,  Adirondack,  Rubicund,  Ruby  and  Snowflake.  The  latter 
variety  is  still  rememl)ered  for  its  high  table  quality,  but  on  account 
of  a  weak  habit  of  growth  and  comparative  unproductiveness,  it 
has  practically  gone  out  of  cultivation,  at  least  in  a  commercial 
way.  The  other  varieties  mentioned  were  relatively  short-lived. 
Unfortuiiately  for  plant  breeding,  Pringle  abandoned  this  field 
of  endeavor  just  when  his  productive  powers  were  at  their  zenith. 
He  became  a  botanical  collector  and  explorer,  in  which  pursuit 
he  was  so  successful  as  to  earn  the  title  of  "Prince  of  collectors." 

In  1876  Robert  Fenn,  one  of  England's  famous  potato  breeders 
published  under  the  caption  of  "Loohlng  Bacl-"°  some  very  inter- 
esting correspondence  between  himself  and  Pringle  relative  to 
potato  breeding.  The  following  quotation  from  Pringle's  letter 
under  date  of  January  5,  1876,  indicates  how  thoroughly  imbued 
he  was  with  the  subject  of  potato  breeding : 

"Twenty  years  ago  there  was  little  disparity,  as  I  suppose,  between 
English  and  American  potatoes.  The  majority  of  the  varieties  which 
we  now  employ,  or  certainly  those  Avhich  are  grown  most  extensively,  have 
originated  since  that  time,  and  have  descended  from  semi-domesticated 
varieties  from  South  America.  Hybridization  of  species  has  been  one  of 
my  aims  Besides  the  original  species  from  the  Andes,  Solanum  tuberosum, 
I  cultivated  one,  very  distinct,  from  our  western  territory  of  New  Mexico, 


388  POTATO  BREEDING  AND  SELECTION 

N.  Fendleri.  As  yet,  all  my  pains  taken  to  impregnate  it  with  pollen  of 
the  cultivated  species  has  proved  unavailing,  though  partially  developed 
fruits  have  followed  my  operations,  only  to  fall  away,  however,  before 
maturity.  When  I  learn  the  conditions  which  the  plant  requires,  and 
more  fully  meet  them,  I  shall  succeed,  doubtless.  Peru  can  furnish  still 
another  species,  ;S'.  Montanum  (vide  Bot.  Mag.)  and  I  am  very  anxious  to 
secure  it." 

This  glimpse  of  Pringle's  work  serves  to  show  the  thoroughness 
with  which  he  attacked  the  potato-l)reeding  problems  of  his  day; 
and  one  can  hardly  refrain  from  indulging  in  retrospect  as  to  what 
he  might  have  accomplished  had  he  continued  his  breeding  work. 

The  work  of  C.  W.  Brownell  of  Essex,  Vermont,  thougli 
not  of  as  high  an  order  as  that  of  Pringle,  extended  over  a  some- 
what longer  period  and  his  introductions  are  more  numerous.  The 
best  known  varieties  are  Beauty,  Best,  Centennial,  Early  Telephone, 
Eureka,  Superior,  Winner  and  Vermont  Beauty  (Beauty  of  Ver- 
mont). So  far  as  known,  Brownell  did  not  make  any  arti- 
ficial crosses. 

Albert  Rand  of  Shelburne,  and  later  of  Bristol,  Vermont, 
came  more  nearly  following  the  same  line  of  breeding  as  that  of 
Pringle.  His  ])roductions  were  Chami)ion,  Delaware,  Matchless, 
Improved  Peachblow  and  Silver  Skin. 

O.  H.  Alexander  of  Charlotte,  Vermont,  was  a  seedsman  as 
well  as  a  plant  breeder,  and  it  is  a  little  difficult  to  determine 
whether  some  of  his  introductions  were  of  his  own  origination  or  not. 
So  far  as  known,  he  did  not  cross-pollinate  potato  blossoms.  The 
seedlings  that  he  originated  were  either  grown  from  naturally  fer- 
tilized seed  balls  or  from  hybridized  seed  produced  by  others.  His 
introductions  were  rather  numerous  and  one  of  them,  at  least,  is 
extensively  grown.  The  list  is  as  follows :  Charles  Downing,  Dakota 
Eed,  Everitt,  Garfield,  Green  Mountain,  Eeliance,  Trophy,  White 
Mountain.  Of  this  list,  the  Green  Mountain  is  by  far  the  most 
important,  as  it  and  its  prototypes  are  among  the  most  widely 
grown  varieties  in  the  northeastern  United  States. 

The  productions  of  Gleason  and  Heffron  were  neither  numer- 
ous nor  important.  The  former  originated  the  Willard,  and 
the  latter  the  Chicago  Market  and  Climax.  Heffron  was  closely 
associated  with  Goodrich  toward  the  close  of  the  latter's  life  and 
assisted  in  introducing  some  of  his  seedlings. 

Luther  Burbank's  claim  to  notice,  in  connection  with  potato- 
breeding  work  of  this  period,  lies  in  the  fact  that  he  was  fortunate 
enough  to  produce  a  seedling,  named  after  himself,  which  became 


THE  WORK  OF  E.  S.  CARMAN  389 

widely  known  and  is  still  extensively  grown  in  some  sections, 
particularly  in  California.  The  story  of  the  origin  of  the  Burbank 
Seedling  is  not  indicative  of  any  particular  effort  on  Burbank's 
part.  It  is  simply  a  story  of  the  discovery  of  a  naturally  fertilized 
seed  ball  on  an  Early  Eose  plant  in  his  mother's  garden  at  Lan- 
caster, Massachusetts,  in  1873;  its  subsequent  loss  and  re-discovery 
on  the  ground  beneath  the  plant;  the  growing  of  23  seedling  plants 
from  this  berry ;  and  the  selection  of  the  most  promising  one  which, 
three  years  later,  1876,  was  introduced  by  Gregory  of  Marblehead, 
Massachusetts,  under  the  name  of  Burbank's  Seedling.  Contrast 
this  record  with  that  of  Goodrich,  who  grew  about  12,000  seedlings 
extending  over  a  period  of  about  15  years,  and  out  of  all  this 
number  failed  to  produce  any  that  brought  him  as  much  lasting 
fame  as  did  Burbank's  Seedling. 

This  simply  serves  to  illustrate  a  point  too  frequently  lost  sight 
of  by  the  plant  breeder,  and  that  is,  that  those  who  follow  the  pion- 
eer usually  reap  the  richest  reward.  Bresee  produced  an  Early 
Eose  from  Goodrich's  Garnet  Chili,  and  Burbank  produced  his 
seedling  from  the  Early  Eose.  In  like  manner,  iVlfred  Eeese,  in 
1871,  obtained  the  Early  Ohio  from  a  naturally  fertilized  seed 
ball  of  the  Early  Eose,  a  variety  that  is  still  extensively  grown  in 
the  Eed  Eiver  Valley  in  Minnesota  and  North  Dakota,  in  the 
Kaw  Valley  in  Kansas,  and  many  other  localities  in  the  central 
and  western  states. 

Coy's  Productions. — E.  L,  Coy  of  Hebron,  New  York,  obtained 
the  Early  Beauty  of  Hebron  in  the  early  seventies  from  a  naturally 
fertilized  seed  ball  of  the  Garnet  Chili.  This  variety  was  intro- 
duced in  1878,  and  for  a  considerable  period  was  rather  extensively 
grown.  It  was  a  heavy  producer  of  fair  quality  potatoes,  but  both 
vine  and  tuber  were  extremely  susceptible  to  late  blight.  At  the 
present  time  it  is  little  cultivated.  Coy  was  also  the  originator  of 
the  following  varieties :  Late  Beauty  of  Hebron,  Early  Puritan, 
Empire  State,  Late  Eose,  Noroton  Beauty,  Thorburn,  Vaughan 
and  White  Elephant. 

Thus,  within  a  comparatively  few  years,  there  was  developed 
from  the  Garnet  Chili,  and  its  daughter  the  Early  Eose,  several 
varieties  that  are  still  extensively  grown,  and  from  which  many 
others  have  sprung  to  enrich  our  agriculture. 

The  work  of  E.  S.  Carman,  former  editor  of  The  Rural  Netv 
Yorker,  is  of  extreme  interest  to  the   plant  breeder  in  that  lie 


390  POTATO  BREEDING  AND  SELECTION 

introduced  an  entirely  different  strain  of  seedling  potatoes  into  our 
agriculture.  So  far  as  we  are  able  to  judge,  Carman's  varieties  do 
not  possess  the  same  blood  as  do  those  which  have  sprung  from 
the  Garnet  Chili  or  the  Jersey  Peachblow.  Unfortunately,  Carman 
did  not  keep  careful  records  of  his  work,  and  the  exact  parentage 
of  his  seedlings  is  not  known.  He  admits  that  he  failed  to  make 
any  crosses  between  the  varieties  in  his  collection,  and,  according 
to  his  own  account,  even  failed  in  the  earlier  years  of  his  work  to 
find  any  naturall}'  fertilized  seed  balls.  This  lack  of  success  in 
securing  seeds  led  him  to  advertise  widely  in  The  Rural  New 
Yorl'ei^  for  potato  seed  balls.  In  response  to  this  appeal,  some  seed 
was  received  from  Euroj)e,  and  from  these  he  produced  seedlings 
that,  in  turn,  bore  seed  balls;  and  from  this  seed  he  obtained  his 
Carman  Nos.  1,  2  and  3.  On  its  introduction.  Carman  No.  2  was 
given  the  name  of  Rural  New  Yorker  No.  2.  Sir  Walter  Raleigh 
was  produced  from  seed  of  the  Rural  New  Yorker  No.  2.  Carman's 
productions  have  added  millions  of  dollars  to  the  productive  wealth 
of  the  States  of  New  York,  Michigan,  Wisconsin,  Iowa  and  Minne- 
sota, and  as  yet  there  seems  to  be  no  diminution  in  their  vigor. 

Breeders  From  a  Few  States. — Thus  far  all  of  the  potato 
breeders  discussed  have  been  residents  of  some  half-dozen  states, 
all  of  which,  except  Ohio  and  New  York  belong  to  the  New  England 
group.  The  chief  centres  were  New  York  and  Vermont.  It  would 
hardly  be  fair,  however,  to  claim  that  nothing  liad  been  attempted 
in  the  Middle  West  in  tlie  development  of  new  varieties.  Among 
those  who  have  been  most  prominently  identified  with  this  work 
might  be  mentioned  the  names  of  Martin  Bovee  of  Michigan, 
Thomas  Craine  of  Wisconsin,  and  F.  B.  Van  Ornam  of  Iowa. 
Bovee  originated  Bovee,  Early  Michigan  and  Pingree.  Craine 
gave  us  June  Eating,  Keeper  and  Potentate.  Van  Ornam's  con- 
tributions were  Extra  Early  (Burpee's)   and  Great  Divide. 

In  concluding  this  enumeration  of  nineteenth  century  potato 
breeders,  we  do  not  claim  to  have  mentioned  all  who  are  entitled 
to  recognition,  nor  that  the  list  of  varieties  given  represents  all 
that  each  of  them  originated.  The  object  in  mind  has  been  rather 
to  give  a  running  history  of  potato  breeding  from  the  middle  of 
the  century  to  its  close,  in  order  to  show  what  influence  each  of 
the  men  mentioned  may  have  exerted  on  the  potato  industry  of 
the  country  as  a  whole,  and  to  bring  together  in  a  concrete  way 
such  data  as  would  seem  to  be  most  important  to  those  inter- 
ested in  potato  breeding. 


FENN'S  PRODUCTIONS  391 

Potato  Breeding  in  Europe. — It  is  interesting  to  note  that 
potato-breeding  activities  in  Europe  were  coincident  with  those  in 
America.  That  this  should  have  been  the  case  is  not  unnatural, 
because  the  same  severe  losses  from  late  blight  had  been  sustained 
by  the  European  growers,  and  therefore  the  same  necessitj'  existed 
for  the  im])rovement  of  the  potato  through  the  development  of 
more  vigorous  growing  varieties. 

Work  of  Paterson. — In  Great  Britain  the  name  of  William 
Paterson  of  Dundee,  Scotland,  stands  out  prominently  as  a  pioneer 
in  potato  breeding  work.  According  to  Wright  and  Castle,-''  he 
was  probably  the  first  person  to  cross-pollinate  the  potato. 

His  first  experiments  were  made  in  1826,  but  it  was  not  until 
1856  that  he  produced  anything  of  merit.  Paterson's  Victoria 
(1856)  is  regarded  by  many  as  the  beginning  of  distinct  progress 
in  potato  breeding  in  Great  Britain.  In  addition  to  the  Victoria, 
Paterson  originated  many  others,  but  his  fame  as  a  breeder  will 
always  rest  on  that  variety. 

Fenn's  Productions. — In  many  respects  the  work  of  Eobert 
Fenn,  in  England,  is  very  similar  to  that  of  Pringle,  in  America. 
They  were  both  intensely  interested  in  potato  breeding  and  for  a 
time  kept  up  an  active  correspondence.  Some  reference  has  al- 
ready been  made  to  this  correspondence,  and  certain  extracts  given 
of  one  of  Pringle's  letters.  Similar  extracts  are  now  presented 
from  one  of  Fenn's  letter  to  Pringle  under  date  of  January  27, 
1876,  the  citation  being  taken  from  Fenn's  article  "Looking  Back," 
previously  given.     In  this  letter  he  says: 

"I  seein  already  to  have  entered  into  your  ideas  concerning  the 
mingling  of  blood  of  English  and  American  kinds.  For  three  years 
consecutively,  though  as  yet  ineffectually,  I  have  tried  to  cross  my  Rector 
of  Woodstock  seedling  with  your  Rnowflake.  as  being  the  very  best  of  the 
American  varieties  sent  over  to  us.  Snowflake  refuses  to  produce  me  a 
globule  of  pollen  or  to  become  impregnated ...  .This  also  has  been  the 
case  with  other  American  varieties,  till  this  season  a  stool  of  that  shy 
bloomer,  Willard's  Seedling,  threw  a  stalk  of  flowers  and.  to  my  great 
satisfaction,  gave  me  some  pollen  upon  my  thumb  nail.  I  immediately 
applied  the  dust  to  the  pistils  of  three  prepared  florets  of  my  seedling 
Bountiful,  and,  in  a  few  days.  I  had  the  inexpressible  satisfaction  to  find 
impregnation  complete,  and  the  berries  steadily  growing.  Again,  some 
three  years  ago,  after  applying  the  pollen  of  Bountiful  to  some  hundreds 
of  pistils  on  the  blossoms  of  the  American  Late  Rose,  I  was  in  despair 
until  two  farewell  bunches  of  flowers  appeared  in  the  row,  when,  as  a  last 
resort,  I  again  applied  the  pollen  of  Bountiful  and  perseverance  gave  me 
five  impregnated  berries." 


392  POTATO  BREEDLNG  AND  SELECTION 

Fenn's  first  crosses  were  made  in  1857  between  Old  Red  Regent 
and  American  Black  Kidney,  also  between  American  Black  Kidney 
and  English  Red  Regent.  He  used  American  varieties  freely  in 
his  crosses. 

James  Clark  should  also  have  a  place  among  potato  breeders 
of  his  time  on  account  of  his  Magnum  Bonum,  which,  according 
to  Dean,^  was  the  result  of  a  cross  between  Early  Rose  and 
Paterson's  Victoria  made  in  the  early  seventies.  It  was  intro- 
duced by  Sutton  in  1876.  For  a  number  of  years,  the  Magnum 
Bonum  was  very  popular  in  Great  Britain  and  elsewhere  on  account 
of  the  fact  that  it  was  a  strong  grower,  comparatively  free  from 
disease,  productive  and  of  fairly  good  quality.  The  blood  of  the 
Magnum  Bonum  represented  the  best  of  American  and  Brit- 
ish varieties. 

Findlay's  Up-to-Date,  introduced  toward  the  close  of  the 
nineteenth  century,  established  such  a  reputation  for  this  famous 
potato  breeder  as  to  make  his  subsequent  productions  very  much 
sought  after.  These  will  be  noted  uiider  twentieth  century 
development.  The  Up-to-Date  very  largely  supplanted  Clark's 
Magnum  Bonum. 

Other  British  Breeders. — The  good  work  done  by  Carter, 
Chapman,  Daniels,  Fidler,  Forbes,  Harris,  Kerr,  Sharpe,  Sutton 
and  Webb  attests  to  the  deep  interest  taken  in  the  improvement 
of  the  potato  by  the  potato  breeders  of  Great  Britain. 

The  Vilmorins  in  France  have  always  been  active  in  the 
conduct  of  plant  breeding  work.  As  a  rule,  however,  there  does 
not  seem  to  have  been  as  much  interest  taken  in  the  potato  by  the 
French  plant  breeders  as  in  Great  Britain  and  Germany. 

The  work  of  Wilhelm  Richter,  in  Germany,  affords  a  strik- 
ing example  of  what  may  be  accomplished  l)y  concentration  of  effort 
upon  a  certain  specific  thing.  In  1869  Richter  became  greatly 
interested  in  the  improvement  of  the  potato.^'"'  At  that  time, 
the  starch  content  of  the  potato  in  Saxony  ran  from  9  to  11.5  per 
cent.  Potatoes  of  English  origin  dominated  the  German  market. 
In  1875,  at  the  exhibition  of  Allenburg,  Richter  was  able  to  show 
a  number  of  promising  seedlings,  such  as  Richter's  Imperator, 
Precious  Stone  and  others.  His  Imperator  proved  to  be  a  particu- 
larly valuable  variety,  and  Improved  Imperator  is  still  a  leading 
German  variety.  Paulsen  and  Cimbal  have  also  contributed  much 
to  the  development  and  improvement  of  the  potato  in  Germany. 


TWENTIETH  CENTURY  PROGRESS  393 

Twentieth  Century  Progress  in  Potato  Breeding. — In  many 

respects,  the  actual  progress  made  in  potato  breeding  in  this 
country  since  1900  falls  far  short  of  that  made  from  1851  to  1890. 
Convincing  evidence  of  the  truth  of  this  assertion  may  be  obtained 
by  a  careful  j^erusal  of  the  seed  catalogues  from  1867  to  1890.  No 
such  activity  can  be  sho"\\ai  in  any  later  period,  nor  can  anything 
like  as  good  descriptions  of  the  newer  introductions  be  found  in 
our  present  day  catalogues.  This  apparent  decadence  of  interest 
in  potato  breeding  may  be  partially  explained  by  the  fact  that, 
during  the  nineties,  the  extremely  low  prices  of  farm  products 
had  a  depressing  effect  on  the  potato  industry. 

Another  factor  which  may  have  served  to  lessen  interest  in 
potato  breeding  was  that,  with  the  introduction  of  the  Green 
Mountain  and  Eural  types  of  potatoes,  so  admirably  adapted  as  a 
late  crop  in  the  northeastern  United  States,  there  was  little 
incentive  to  indulge  in  this  line  of  effort. 

In  Europe,  on  the  other  hand,  during  the  first  few  years  of 
the  century,  the  world  never  witnessed,  and  probably  "\vill  never 
again  witness,  such  wild  excitement  as  prevailed  during  the  intro- 
duction of  Sutton's  Discovery,  and  Findlay's  Northern  Star  and 
Eldorado.  The  high  prices  paid  for  these  varieties  were  largely 
due  to  the  fact  that  they  were  heralded  far  and  wide  as  being 
almost  immune  to  late  blight. 

A  similar  mania  j^revailed  in  America  during  the  years  18G7 
to  1869.  A  sale  is  recorded^^  in  the  Spring  of  1868  of  150  bushels 
of  the  Early  Eose  for  $1,000  or  an  average  price  of  $66.66  per 
bushel.  The  May  issue  of  the  American  Agriculturist  1868,  p.  153, 
contains  the  announcement  that  a  portion  of  the  150  bushels  had 
been  re-sold  at  $80  per  bushel. 

Beecher,^  in  his  essay  on  "The  Potato  Mania,"  states  that  as 
high  as  $50  per  tuber  was  paid  for  Bresee's  King-of-the-Earlies. 

Although  a  number  of  new  varieties  have  been  introduced  by 
American  seedsmen  since  1900,  it  can  hardly  be  claimed  that  much 
progress  has  been  made  along  this  line.  The  two  acquisitions  that 
offer  much  promise  are  the  russet  type  of  the  Burbank  and  Rural 
group.  Nothing  definite  is  known  about  the  origin  of  the  Eusset 
Burbank.  So  far  as  it  is  possible  to  determine,  the  Eusset  Eural 
appears  to  have  originated  in  Michigan.  This  iy^e  of  Eural  has 
recently  been  accepted  by  growers  in  some  sections  of  Michigan 
as  their  standard  commercial  variety. 


394  POTATO  BREEDING  AND  SELECTION 

Lack  of  familiarity  with  the  newer  introductions  abroad,  other 
than  those  mentioned,  does  not  permit  of  making  comparisons  be- 
tween them  and  those  which  were  being  grown  commercially  prior 
to  1900.  There  can  hardly  be  said  to  be  any  lack  of  interest  among 
potato  breeders,  as  will  be  indicated  by  some  of  the  names  here 
presented,  all  of  whom  have  been  more  or  less  actively  engaged 
in  an  attempt  to  improve  the  potato.  This  list  is  as  follows : 
Berthault,  Dean,  Findlay,  Freckmann,  Seelliorst,  Heckel,  Paton, 
Salaman,  Sutton,  Taylor  and  Wilson.  It  is  needless  to  say  that 
this  list  by  no  means  represents  those  who  are  actively  engaged 
in  potato-breeding  work. 

Difficulties  Involved  in  Potato  Breeding. — One  of  the  chief 
difficulties  confronting  the  potato  breeder  is  due  to  the  fact  that 
so  many  of  our  most  desirable  commercial  varieties  bloom  very 
sparingly,  if  at  all,  in  some  localities,  and  that,  as  a  rule,  the 
most  of  them  do  not  produce  viable  pollen  in  sufficient  amount  to 
impregnate  the  ovaries  of  the  flowers  to  which  it  is  applied.  This 
statement  applies  almost  equally  well  to  the  free  blooming  as  to  the 
shy  blooming  varieties. 

Another  difficulty  encountered  ])y  the  breeder  is  that  untoward 
seasonal  conditions  at  the  time  the  blossom  buds  are  forming  may 
wholly  prevent  the  full  development  of  the  flower,  and,  conse- 
quently, the  opportunity  to  make  crosses  is  lost. 

A  further  drawback  to  progressive  work  in  potato  breeding  is 
due  to  what  might  be  termed  the  irony  of  fate,  in  that  the  few 
varieties  which  do  produce  ample  viable  pollen  are  more  or  less 
unsatisfactory  from  a  commercial  standpoint,  with  the  result  that 
the  seedlings  derived  from  the  use  of  such  ])ollen  inherit  many  of 
the  undesirable  characteristics  of  their  male  parent. 

Flowering  Habits. — In  discussing  the  llowering  habits  of  our 
commercial  varieties  East^  makes  the  following  statement : 

"If  we  regard  blossoming  as  invariable  at  some  period  of  tbeir  life 
under  the  proper  conditions,  we  can  then  divide  potato  varieties  into 
several  classes. 

1.  Varieties  whose  buds  drop  off  without  opening. 

2.  Varieties   in  which  a  few   flowers   open,   but   fall  immediately. 

3.  Varieties  whose  flowers  persist  several  days,  but  rarely  produce 
viable  pollen." 

He  estimates  that  about  GO  per  cent  of  our  named  varieties 
belong  to  the  first  class,  and,  of  the  varieties  that  do  bloom,  only  60 
per  cent  have  their  blossoms  persistent  for  more  than  one  day. 


ABUNDANCE  AND  VIABILITY  OF  THE  POLLEN  395 

East  further  found  that  unseleeted  two-year-old  seedlings  gave 
nearly  the  same  percentage  of  plants  that  dropped  their  huds  before 
opening,  the  figures  being  56  and  4-i,  respectively.  From  these  data 
he  made  the  following  deductions : 

"  This  approximately  equal  percentage  of  the  different  classes,  both 
in  seedlings  and  in  named  varieties,  indicates  that  their  sexual  differences 
are  inherited  as  distinct  characters,  and  are  not  due  to  increased 
tuber  formation." 

Observations  of  the  writer  do  not  substantiate  those  of  East 
relative  to  the  percentage  of  non-flowering  varieties,  nor  do  they 
necessarily  refute  them,  if  we  regard  his  data  as  merely  applying 
to  the  particular  locality  in  which  his  studies  were  made.  The 
percentage  of  varieties  belonging  to  any  given  class  varies  with  the 
region,  and  is  very  largely  dependent  upon  the  climatic  conditions 
under  which  the  plants  are  grown.  In  a  previous  publication^^ 
the  writer  made  the  following  statement : 

"Most  varieties  will  produce  some  blossoms  when  grown  under  optimum 
conditions  for  the  normal  development  of  the  plant,  particularly  if  these 
conditions  prevail  during  the  stage  at  which  flower  buds  are  formed.  In 
any  considerable  varietal  collection  it  is  inevitable  that  many  varieties 
should  find   the   conditions   unsuitable   for   their   maximum   development." 

As  a  result  of  over  a  quarter  of  a  century's  intimacy  with  a 
large  varietal  collection,  the  writer  has  come  to  recognize  the  fact 
that  varieties  belonging  to  certain  groups  or  classes  of  potatoes 
bloom  freely  or  sparsely  according  to  the  particular  group  to  which 
they  belong.  For  example,  the  members  of  the  Irish  Cobbler,  Early 
Michigan,  Early  Eose,  Beauty  of  Hebron,  Green  Mountain,  Rural, 
Peachblow  and  Up-to-Date  groups  bloom  profusely  to  very  pro- 
fusely in  northern  Maine;  those  of  the  Early  Ohio  and  Burbank 
groups  are  only  moderate  bloomers,  while  those  of  the  Triumph  and 
Pearl  grouj)s  are  very  sparse  liloomers. 

Abundance  and  Viability  of  the  Pollen. — Great  variations  are 
found  in  varieties  with  respect  to  the  quantity  and  viability  of  the 
pollen  produced  by  them.  During  the  years  1903  to  1907  the 
writer  had  an  opportunity  to  observe  the  behavior  of  a  Avild  Mexican 
species.  Solarium  polyadenium,  with  respect  to  the  formation  of  seed 
balls.  It  was  noted  that  while  it  bloomed  rather  freely  throughout 
the  growing  season  it  seldom  developed  seed  balls  until  the  latter 
part  of  the  summer.  Examination  of  the  stamens  showed  that  it 
was  not  due  to  lack  of  pollen,  and  that  its  failure  to  develop  seed 


396  POTATO  BREEDING  AND  SELECTION 

balls  was  apparently  due  to  a  lack  of  viable  pollen.  In  plant  breed- 
ing studies  extending  over  a  })eriod  of  sixteen  years  it  has  been  the 
writer's  privilege  to  examine  the  stamens  of  a  great  many  varieties, 
and  in  but  few  instances  has  an  abundance  of  viable  polle]i  been 
found.  The  data  show  a  very  much  larger  proportion  of  foreign 
varieties  producing  viable  pollen  than  of  x\nierican  varieties.  Of 
the  many  varieties  studied  in  the  twelve  groups  mentioned,  only 
four  were  noted  which  could  lie  regarded  as  dependable  sources 
from  which  to  obtain  viable  pollen.  These  four  American  varie- 
ties were  Early  Silver  Skin,  Keeper,  McCormick  and  Bound 
Pinkeye,  all  of  them  undesirable  from  the  standpoint  of  their  table 
quality,  smoothness  of  surface,  color  of  skin  or  productiveness. 
There  are  times,  however,  when  it  is  possible  to  secure  sufficient 
viable  pollen  to  make  artificial  crosses  from  varieties  belonging 
to  the  Burbank,  Green  Mountain  and  Eural  groups;  and  less 
infrequently  from  the  Irish  Cobbler,  Triumph,  Early  Michigan, 
Early  Eose,  Early  Ohio,  Beauty  of  Hebron  and  Pearl  groups. 
The  Peachblow  group  is  omitted  because  the  McCormick  and  Round 
Pinkeye  are  members  of  that  group.  The  varieties,  Early  Silver 
Skin  and  Keeper,  do  not  fit  into  any  of  the  groups  mentioned. 

More  recently  certain  varieties  of  foreign  origin,  such  as  Busola 
and  Petronius,  have  been-  found  to  produce  an  abundance  of  viable 
pollen  and  they  seem  to  transmit  desirable  qualities  to  their 
offspring. 

In  a  rather  recent  publication  Salaman'''  announces  that  male 
sterility  is  a  dominant  Mendelian  character. 

THE  TECHXIC   OF  rOTATO  BREEDING 

The  first  consideration  in  the  technic  of  plant  breeding  is 
that  of  the  character  of  the  flowers  borne  by  the  plant  which  one 
desires  to  cross.  The  flowers  of  a  plant  are  either  perfect  or  im- 
perfect. Perfect  floAvers  are  those  which  possess  both  stamens 
and  pistils;  imperfect  ones  those  which  are  devoid  of  one  or  the 
other  reproductive  organ  or  organs.  The  potato  plant  bears  perfect 
flowers,  and  is  of  such  simple  structure  as  to  render  the  task  of 
crossing  it  comparatively  easy  (Fig.  205). 

Structure  of  the  Pistil. — The  pistil  of  each  flower  is  morpho- 
logically divided  into  two  parts,  viz.,  the  st3'le  and  the  stigma. 
Each  potato  flower  bears  but  one  pistil  (Fig.  206),  the  style  of 
which  varies  from  six  to  nine  lines  in  length,  and  from  one-third  to 


STRUCTURE  OF  THE  STAMENS  397 

two-thirds  of  a  line  in  diameter.  Usually,  the  shorter  the  style, 
the  fleshier  it  is.  Some  styles  are  greatly  curved,  and  in  some 
varieties  there  is  a  distinct  spiral  twist  as  in  Up-to-Date  and 
Factor.  Others  are  perfectly  straight.  The  two-lobed  stigma  also 
varies  considerably  in  size,  some  being  only  slightly  enlarged  and 
somewhat  cup-shaped,  while  others  are  considerably  enlarged, 
having  well-rounded  lobes  covered  with  short  papilla. 

Structure  of  the  Stamens. — The  potato  flower  normally  pos- 
sesses five  stamens,  but  occasionally  four  or  six  are  noted.  In  some 
varieties  six  stamens  are  of  quite  frequent  occurrence.  The  stamens 
have  short,  thick  iilanicnts  with  laro-e,  tleshv,  erect  anthers,  which 


Fig.  205.— Potato  flower  natural  size  show-  Fig.  206.— Potato  flower  with  sta- 

ing  stamens  and  pistil.  mens  removed  showing  naked  pistil. 

usually  stand  close  together  around  the  style,  like  a  cone  in  the 
centre  of  the  flower  (Fig.  205).  The  anthers  may  vary  from  three 
to  five  lines  in  length  and  one  to  one  and  one-half  lines  in  breadth, 
and  about  one  line  in  thickness.  The  placenta,  which  divides  the 
anther  longitudinally  into  two  equal  cell-like  compartments,  is 
rather  thick  and  fleshy.  The  halves  or  lobes  of  the  anthers  have 
small  terminal  pore  openings  for  the  discharge  of  the  ripe  pollen, 
which  are  produced  on  the  inner  surfaces  of  the  cell.  In  many 
varieties,  the  anthers  are  so  poorly  developed  that  the  terminal 
pores  do  not  open,  though  they  are  not  so  undeveloped  as  to  be 
devoid  of  pollen.  In  such  cases,  the  membranous  outer  covering 
of  each  anther  lobe  or  cell  may  be  slit  open,  and  the  pollen  grains 
scraped  off  into  a  receptacle  by  means  of  a  scalpel,  forceps  or 
needle.  Usually,  however,  such  pollen  is  not  viable,  and  one  should, 
therefore,   reject  such  varieties  for   pollen  purposes.     The   color 


398 


POTATO  BREEDING  AND  SELECTION 


of  the  stamens  varies  greatly  with  different  varieties.  Some  are 
a  pale  lemon-yellow,  while  others  are  a  bright  orange-yellow,  with 
all   the   intergradations   of    color   between   these   two.      Only   one 


A  B 

Fig.  207. — -Potato  flower  cymes.  A  shows  three  floweri  which  micht  bo  used  for  arti- 
ficial pollination,  though  only  the  upper  right  hand  bud  is  at  the  right  stage.  Cyme  B  has 
two  buds  at  right  stage. 


Fig.  208. — Cymes  A  and  B  after  emasculation.    Note  protruding  pistils  in  lower  flow- 
ers of  cyme  A. 

instance  has  come  under  our  observation  in  which  the  color  of  the 
stamens  did  not  answer  to  the  above  description,  and  that  was 
in  the  case  of  a  wild  Mexican  species,  Solarium  cardiophyllum 
lanceolatum,  (Berth.)  Bitter,  where  the  anthers  were  chocolate- 
brown  with  a  slight  tinge  of  purple.    Usually  varieties  with  pale, 


ARTIFICIAL  CROSS-POLLINATION  399 

lemon  anthers  do  not  produce  pollen  freely  and,  as  a  rule,  it  is 
not  viable.  A  considerable  variation  has  also  been  noted  in  the 
turgidity  of  the  anthers,  usually  those  of  a  pale  lemon-yellow  color 
are  less  turgid,  and  are  more  loosely  arranged  around  the  pistil. 
Often  this  looseness  is  in  the  nature  of  a  distinct  curving  outward 
of  the  central  portion  of  the  anther,  the  tips  of  the  anther  clasping 
the  pistil.  Generally  this  type  of  flower  has  one  or  more  defective 
stamens.  On  the  other  hand,  it  has  been  observed  that  some  of 
those  having  a  deep  orange-yellow  color,  like  those  of  Solanum 


Fig.  209. — Emasculating  the  flowers. 

Maglia,  are  so  firm  as  to  be  almost  coriaceous.  Flowers  of  this  class 
seldom,  if  ever,  produce  an  appreciable  quantity  of  pollen  and, 
as  a  rule,  it  is  not  vial}le. 

Artificial  Cross-pollination. — The  actual  process  of  cross- 
pollinating  potato  flowers  is  comparatively  simple;  but  since 
relatively  few  of  our  commercial  varieties  develop  viable  pollen, 
the  percentage  of  success  is  usually  small,  unless  the  operator 
employs  pollen  from  varieties  that  produce  it  freely  and  that  is 
known  to  be  highly  viable. 

The  first  step  in  the  cross-pollination  of  the  potato  is  obviously 
that  of  the  selection  of  the  parent  plants.  Strong,  healthy  plants 
should  be  chosen,  of  a  variety  possessing  certain  definite  characters 
which  it  is  desired  to  combine  with  certain  other  desirable  characters 
of  another  plant.     The  next  step  is  the  selection  and  emasculation 


400 


POTATO  BREEDING  AND  SELECTION 


of  the  llowers  to  which  pollen  is  to  be  applied,  and  the  bagging  of 
the  same  (Figs.  207  to  213). 

The  proper  stage  at  which  to  emasculate  the  flowers  is  usually 
about  24  hours  before  the  buds  normally  open.  This  stage  is 
shown  in  figure  207-B.  The  only  instrument  necessary  for  the 
removal  of  the  stamens  is  a  sharp,  pointed  forceps  (Figs.  209  and 
212).  To  perform  the  operation,  clasp  the  lower  portion  of  the 
bud  between  the  forefinger  and  thumb  of  the  left  hand  and,  with 
the  forceps  held  in  the  right  hand,  slit  open  and  push  back  the 


Fig.  210. — A  simple  anil  handy  pollinating  kit. 

corolla,  after  which  the  fleshy  anthers  can  be  easily  and  quickly 
removed  by  pressing  each  of  them  backward  from  the  pistil  until 
it  snaps  from  its  filament.  Figure  206  shows  a  blossom  from  which 
the  stamens  have  been  removed  in  the  manner  described.  It  is 
usually  desirable  to  emasculate  as  many  flowers  in  each  cyme  as 
are  at  the  right  stage  of  maturity.  All  those  that  are  too  imma- 
ture or  mature  should  be  removed  before  inclosing  those  that  have 
been  emasculated  in  a  paper  bag  (Figs.  209  and  213).  A  one- 
pound  bag,  that  is,  a  paper  sack  having  a  capacity  mark  of  one 
pound  is  large  enough  for  this  purpose  (Fig.  211). 

The  work  of  putting  on  the  sacks  can  be  greatly  facilitated  by 
perforating  the  tops  of  the  sacks  and  running  strings  through 
them,  prior  to  their  use  in  the  field,  as  shown  in  figure  211.  An- 
other feature  that  has  proved  satisfactory  is  that  of  inclosing  with 


ARTIFICIAL  CROSS-POLLINATION 


401 


the  flowers  the  young  shoot  ou  which  the  flower  cyme  is  borne, 
or  where  this  is  not  feasible,  as  much  foliage  as  possible.  The 
iuclosure  of  the  foliage  serves  a  two-fold  purpose,  that  of  protecting 

the  flowers  by  keeping  the 
bag  distended,  and,  in  sup- 
plying moisture  through 
leaf  transpiration. 

The  flowers  are  usually 
ready  for  pollinating  one 
or  two  days  after  emascu- 
lation, depending  upon  the 
stage  of  maturity  when 
emasculated  and  the  char- 
acter of  the  weather  subse- 
quent to  it. 

Salaman^"'  and  East" 
regard  the  covering  of  the 
flowers  with  bags  as  an 
unnecessary  procedure  and 
likely  to  cause  injury  to 
the  pistil.  On  this  subject 
Salaman  says : 

"All  my  work  has  been 
carried  on  without  placing  the 
flowers  in  bags.  The  reasons 
for  not  adopting  special  pre- 
cautions were  that,  when 
bagged,  the  flower  invariably 
drops;  that  bees  and  the  like 
never  approach  a  potato  flower, 
though  a  srnall  fly  often  lives 
in  the  bottom  of  the  corolla; 
that  the  flower  is  con- 
structed for  self-fertilization;  and  that  the  quantity  of  pollen  is  so  scanty 
as  to  render  fertilization  by  the  wind  in  the  highest  degree  improbable." 

East  says : 

"  We  may  conclude  that  if  we  cut  off'  all  the  uppermost  cymes  from 
the  plant  stems,  and  use  for  pollination  only  emasculated  flowers  of  those 
borne  next  in  order,  the  relative  probability  of  our  crosses  being  interfered 
with  is  negligible  for  all  practical  purposes.  This  removes  the  neces- 
sity of  shutting  out  the  light  and  air  circulation  by  means  of  bags.  It  is 
also  worthy  of  note  that  the  chances  of  success  are  much  greater  if 
the  calyx  and  corolla  are  not  removed  during  emasculation,  as  the  style 
is  very  slender  and  is  likely  to  be  injured." 
26 


Fig.  211. — One  pound  paper  bag  ready  for  use. 


402 


POTATO  BREEDING  AND  SELECTION 


While  it  is  true  that  the  pistil  of  the  flower  is  easily  broken  off, 
and  that  few  insects  visit  the  flowers,  it  is  not  necessai-ily  true  that 
the  inclosure  of  the  emasculated  flowers  in  paper  bags  causes  aiiy 
more  of  them  to  drop  off  than  if  left  uncovered,  provided  the  oper- 
ator follows  the  suggestions  given  relative  to  including  as  much 
foliage  with  the  flowers  as  is  possible.  The  beneficial  efi^ect  of  the 
foliage  has  already  been  mentioned. 

Method  of  Collecting  and  Applying  Pollen. — Many  methods 
have  been  pursued  by  the  writer  in  collecting  pollen,  but  none  have 
proved  as  satisfactory  as  the  one  which  is  now  followed.     This 


Fig.  212. — Jarring  the  Fig.  213. — Enclosing  the  impregnated  flowers  in  ija- 

pollen    from    the    anthers    on    per  bag  and  recording  the  cross, 
thumbnail. 

method  consists  in  gathering  the  flowers,  as  needed,  from  the  plants 
which  have  been  selected  as  pollen  parents.  When  a  large  number 
of  emasculated  flowers  are  to  be  crossed  and  different  pollen  parents 
are  to  be  used,  it  has  been  found  expedient,  as  well  as  satisfactory, 
to  collect  a  number  of  flowers  of  the  varieties  desired,  which  are 
at  the  right  stage  of  development,  that  is,  when  the  terminal  pores 
of  the  anthers  have  just  opened.  Each  lot  collected  is  placed  in 
a  separate  bag,  the  bags  being  similar  to  those  used  for  inclosing 
the  emasculated  flowers.  Each  bag  is  properly  labelled  with  the 
name  of  the  variety  or  of  its  field  number.  In  this  way  the  operator 
may  carry  a  considerable  quantity  of  available  material  with  him, 
which  can  be  readily  drawn  upon  as  desired.  When  the  pollen  of 
any  particular  variety  in  the  pollinating  kit  is  desired,  a  flower  is 
selected  from  the  proper  bag,  the  corolla  is  pushed  back  between 


COLLECTING  AND  APPLYING  POLLEN        403 

the  forefinger  and  thumb  of  the  left  hand  and  held  in  such  a 
position  tliat  the  anthers  extend  upward  on  the  thumb  nail  (Fig. 
212).  After  removing  the  pistil,  the  anthers  are  tapped  sharply 
with  the  forceps,  thus  jarring  the  pollen  out  of  the  terminal  pores, 
upon  the  thumb  nail  on  which  it  is  readily  conveyed  to  the  stigmas 
of  the  previously  uncovered  flowers.  The  cross  is  then  recorded 
in  a  field  note  book,  and  its  number  placed  on  a  string  tag,  wdiich 
is  attached  to  the  pedicel  of  the  flower  cyme,  after  which  the  pollin 


"Fig.  214. — Seed  balls  eight  days  after  application  of  pollen. 

ated  flowers  are  again  inclosed  in  the  paper  bag,  care  being  taken 
to  include  as  much  foliage  as  possible,  and  to  avoid  injury  to  the 
pistils.  Generally  the  success  or  failure  of  a  cross  can  be  deter- 
mined in  a  week  from  the  date  of  applying  pollen.  Frequently 
the  seed  balls  at  this  date  will  be  two-thirds  grown  (Fig.  214). 
The  rate  of  development  is  largely  dependent  upon  two  factors, 
viz.,  the  natural  affinity  of  the  plants  crossed,  and  the  amount  of 
viable  pollen  applied  to  the  stigma.  As  a  rule,  the  paper  bag 
should  be  removed  in  seven  days.  At  this  time  the  seed  balls  of 
all  successful  crosses  should  be  inclosed  in  a  loose  cheesecloth  sack, 


404  POTATO  BRKKDING  AND  SELECmON 

securely  tied  to  the  stem  of  the  plaut  in  order  to  keep  it  off  the 
ground,  or  from  breaking  the  flower  stalk,  when  the  plants  begin 
to  mature. 

Percentage  of  Successes. — In  some  studies  made  by  East  (I.e. 
p.  36)  to  determine  whether  the  uppermost,  intermediate  or  lower 
flower  cymes  produced  the  largest  quantity  and  the  most  viable 
pollen,  he  found  that  crosses,  resulting  from  the  application  of 
pollen  from  such  sources  gave  the  following  percentages  of  suc- 
cesses. Upper  C3'mes  ^8  per  cent;  intermediate  52,  and  the  lowest 
cymes  18  per  cent.  He  states  that  these  experiments  were  made 
on  plants  of  a  variety  that  naturally  produced  an  abundance 
of  pollen.  In  our  own  Avork  there  have  been  numerous  failures 
as  well  as  many  successes.  In  the  earlier  years  or  between  1903 
and  1908  very  few  successful  crosses  were  made,  certainly  less  than 
one  per  cent;  but  in  1909  the  percentage  of  successful  crosses  Avas 
quite  large.  This  was  especially  true  in  those  cases  in  which  pollen 
had  been  used  from  a  variety  known  to  produce  a  high  ])ercentage 
of  viable  pollen.  In  some  instances,  every  flower  pollinated  bore 
a  seed  ball. 

The  data  contained  in  the  following  table  embody  the  results 
secured  by  the  writer  in  1909,  while  in  the  employ  of  the  Vermont 
Agricultural  Experiment  Station  and  which  were  prepared  and 
published  in  U.  S.  Department  of  Agriculture  Bui.  195.  A  study 
of  these  data  shows  that  458  seed  balls  were  produced  from  a  total 
of  1,599  crosses.  This  represents  an  average  of  28.6  per  cent 
for  the  Avhole  number  crossed.  When  one  takes  into  consideration 
the  fact  that  a  large  percentage  of  these  crosses  were  entire  failures, 
indicating  the  use  of  worthless  pollen,  they  can  appreciate  the 
fact  that  when  the  proper  pollen  is  ajiplied  to  a  receptive  stigma 
the  percentage  of  successes  will  be  high.  If  we  analyse  these  data 
carefully,  we  find  ample  corroboration  of  the  above  statements. 
The  following  analysis  is  taken  verbatim  from  the  publica- 
tion mentioned. 

"A  study  of  the  table  discloses  some  rather  iiiterestiiii,'  data,  particu- 
larly with  respect  to  the  behavior  of  seed-bearing  plants  when  pol- 
linated with  dillerent  varieties.  In  the  first  cross  recorded,  Oeheinirat 
Theil  X  Keeper,  six  flowers  were  pollinated  and  five  seed  balls  were 
developed  from  which  r)02  tuber-bearing  plants  Avere  produced.  The 
same  variety  when  mated  with  XX  ICarly  developed  only  one  seed  ball 
from  11  pollinated  flowers,  and  this  did  not  produce  a  single  tuber-bearing 
plant.  When  crossed  with  Holanum  Maglia,  a  wild  South  American  species, 
it  failed  to  set  fruit;  and  the  same  negative  results  were  obtained  when 


RECORD  OF  POTATO  CROSSES 


405 


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406 


POTATO  BREEDING  AND  SELECTION 


pollen  of  the  unnamed  IMexican  species  of  Solanum  was  used.  We  know 
that  8.  Maglia  produces  pollen  very  sparingly  and  that  frequent  attempts 
to  germinate  the  pollen  in  the  laboratory  have  been  unsuccessful.  The 
Mexican  species  is  known  to  produce  viable  pollen  in  abundance,  how- 
ever, so  that  in  this  case  the  failure  to  set  fruit  was  probably  a  clear 
example  of  non-uflinity.  The  next  female  parent,  Sophie,  crossed  with 
Keeper,  gave  excellent  results.  Sophie  is  a  German  variety  possessing 
qualities  of   vine  and   tuber   strongly   resistant   to   late   blight.      From   20 


Fia.  215. — A  South  American  variety  with  clusters  of  naturally  fertilized  seed  balls. 

pollinated  flowers  16  seed  balls  were  developed.  The  seed  from  the  16 
seed  balls  produced  2,244  tuber  bearing  plants,  or  an  average  of  140.3  plants 
per  berry.  The  4  pollinated  flowers  of  Sophie  X  Fuerst  Bismarck  failed 
to  develop  a  single  berry.  A  similar  result  was  obtained  from  8  flowers 
pollinated  with  Empire  State  and  from  4  pollinated  with  Garnet  Chili. 
Sophie  X  Irish  Seedling  produced  4  seed  balls  from  the  4  flowers  pollinated. 
The  seeds  from  these  berries  gave  707  tulier  bearing  plants,  or  an  average 
of  176.8  plants  per  berry.  Three  flowers  pollinated  with  Venezuela  failed  to 
set  fruit.    It  is  clearly  evident  that  the  varieties  Fuerst  Bismarck,  Empire 


PERCENTAGE  OF  SUCCESSES 


407 


State,  Garnet  Chili  and  Venezuela  either  did  not  develop  viable  pollen  or 
the  pollen  tubes  were  unal)le  to  reach  the  ovules  of  the  flower.  It  is  known 
that  all  of  these  varieties  produce  pollen  sparingly,  and  it  is  probable  that 
an  insufficient  quantity  of  viable  pollen  was  present  to  efl'ect  the  cross. 
"  In  the  first  cross  of  the  third  seed  parent,  Professor  Maerker  X  Apollo, 
both  the  seed  and  pollen  parents  are  of  German  origin,  the  latter  being 
one  of  the  most  disease-resistant  varieties  in  the  collection.  Nine  seed 
balls  are  recorded  from  12  flowers  pollinated  and  275  tuber-bearing  plants 


Fig.  216. — ^An  Irish  Cobbler  plant  bearing  several  clusters  of  seed  balls  the  result  of 
artificial  application  of  pollen.     One  cheesecloth  sack  removed  to  show  the  berries. 

were  obtained  from  this  lot,  or  an  average  of  30.6  plants  per  berry. 
Fifteen  flowers  pollinated  with  pollen  from  Early  Silverskin  produced  15 
seed  balls,  from  which  555  plants  were  obtained,"  an  average  of  37  plants 
per  berry.  When  crossed  with  Keeper,  12  seed  balls  were  developed  from 
13  flowers  and  these,  gave  320  plants,  or  an  average  of  27.2  plants  per 
berry.     Pollen  from  Rand's  Peachblow  proved  ineffective. 

"  It  is  interesting  to  compare  the  results  from  the  two  crosses, 
Sophie  X  Keeper  and  Professor  Maerker  X  Keeper.  In  the  first  instance 
the  percentage  of  success  is  80  and  in  the  latter  92.3.    Carrying  the  compari- 


408  POTATO  BREEDING  AND  SELECTION 


\ 


Fig.  217. — Several  seed  balls  showing  different  views  of  the  fruit  or  berry,  also  the 
position  and  relative  size  of  the  seeds.    Half  size. 


REMOVING  THE  SEEDS 


409 


son  farther,  however,  we  find  that  the  first  cross  averaged  over  140  plants 
per  berry,  while  the  latter  averaged  only  27.2.  These  data  make  it  at  once 
apparent  that  some  varieties  develop  fewer  ovules  than  others." 

Gathering  the  Seed  Balls. — The  seed  balls  should  be  allowed 
to  remain  on  the  plant  until  they  are  mature  (Figs.  215  and  216), 
or  until  danger  from  frost  makes  it  desirable  to  gather  them.  When 
gathered  they  should  be  placed  in  a  moderately  warm  room  to 
insure  thorough  ripening.  Unless  the  cluster  of  seed  balls  is 
large,  they  are  allowed  to  remain  in  the  sack  until  they  are  thor- 
oughly ripe.  Most  seed  balls,  when  ripe,  are  usually  of  a  pale 
lemon-yellow  color;  but  some  of  the  foreign  varieties,  or  those 


Fig.  218. — Seedling  potatoes  ready  to  be  potted  off  or  pricked  out  into  flats. 

having    foreign    blood    in    their    parentage,    are    of    a    purplish- 
black   color. 

Removing  the  Seeds. — The  usual  practice  is  to  remove  the 
seeds  as  soon  as  the  seed  balls  are  ripe  (Fig.  217).  This  is  most 
easily  accomplished  by  crushing  the  seed  balls  into  a  pulp,  and 
dropping  them  into  a  vessel  of  water  in  a  warm  room.  They  should 
be  allowed  to  remain  in  the  water  for  a  few  days,  or  until  sufficient 
fermentation  takes  place  to  cause  the  pulp  to  rise  to  the  top. 
Frequent  stirring  of  the  contents  of  the  vessel  during  this  time 
will  hasten  the  separation  of  the  seeds  from  the  pulp.  When  the 
seeds  are  largely  separated  from  the  pulp,  the  latter  may  be  floated 
ofE  the  top  of  the  vessel  by  running  water  into  it;  after  this  the 
water  can  be  poured  off  through  a  strainer  or  a  cheesecloth  to  collect 
the  seeds,  which  should  then  be  dried  in  a  moderately  warm  room. 
When  dry,  they  should  be  placed  in  a  packet  and  properly  labelled. 


410 


POTATO  BREEDING  AND  SELECTION 


In  this  condition,  they  may,  if  so  desired,  he  held  several  years, 
without  material  lessening  of  their  viability. 

Method  of  Growing  Seedlings. — Various  methods  may  be 
employed  in  the  growing  of  potato  seedlings.  The  one  practised 
by  the  writer  is  that  of  sowing  the  seed  in  flats  or  earthen  seedpans 
in  the  greenhouse  about  the  last  of  March,  the  soil  used  being  a 
light,  sandy  loam  of  moderate  fertility.     The  seeds  are  sown  in 


Pig.  21 'A 
than  the  average. 


iiotato  seedlings.    Th 


about  the  same  nuinner  as  pepper  or  tomato  seeds,  and  covered  to 
a  depth  of  about  one-eighth  of  an  inch.  Under  favorable  con- 
ditions, well-matured  seed  will  begin  to  germinate  in  from  4  to  6 
days,  and  in  10  days  to  two  weeks  most  of  the  seeds  will  have  started 
to  grow.  In  from  four  to  five  weeks  they  will  be  ready  to  trans- 
plant (Fig.  218)  to  other  flats  or  to  be  potted  off  into  two  and  one- 
half-inch  paraffin  paper  pots.  With  careful  attention  to  watering 
and  room  temperature,  these  plants  should  be  ready  to  transplant 
into  the  open  about  the  last  of  May  or  first  of  June  (Fig.  219). 
At  this  time,  if  well  grown,  they  should  be  stocky  and  thrifty 
plants  of  from  4  to  5  inches  in  height.     A  night  temperature  of 


HARVESTING  THE  SEEDLINGS  411 

from  55  to  60  degrees  ¥.,  with  a  rise  of  20  degrees  during  sunshiny 
days  and  10  degrees  in  cloudy  ones,  will  insure  a  moderate  and 
healthy  development  of  the  plants  in  the  greenhouse. 

The  foregoing  outline  of  procedure  is  not  intended  to  convey 
to  the  reader  the  impression  that  a  greenhouse  is  necessary  to  start 
seedling  potatoes.  They  can  be  grown  in  a  hotbed,  or  they  may 
be  started  in  the  living  room  of  the  house  or  anywhere  else  in 
which  there  is  sufficient  heat  and  light,  after  they  germinate.  The 
same  methods  can  be  followed  as  for  tomatoes  or  peppers.  It 
is  desirable  to  start  the  potato  seedlings  early  in  order  to  give 
them  a  long  growing  season,  so  as  to  insure  good  tuber  develop- 
ment the  first  season,  thereby  making  it  possible  to  discard  the 
undesirable  ones  and  thus  reduce  the  number  to  Ite  tested  the 
ensuing  year. 

Field  Culture  of  the  Seedlings. — Do  not  make  the  mistake 
of  planting  the  seedlings  too  close.  Long  experience  has  demon- 
strated that  a  spacing  of  30  by  36  inches  is  none  too  much.  The 
rows  are  spaced  three  feet  apart  and  the  plants  30  inches  in  the 
rows.  Even  at  this  distance,  it  will  often  be  found  that  many 
of  the  plants  will  more  than  cover  the  space  allotted  to  them ;  their 
long,  tuber-l)earing  stolons  will  intermingle,  making  it  difficult 
to  distinguish  whether  the  tubers  belong  to  the  one  or  the  other 
of  the  two  adjacent  plants  in  the  row.  The  culture  accorded  the 
seedling  plants,  after  transferring  them  to  the  field,  is  not  essen- 
tially different  to  that  which  should  be  given  to  commercial  varie- 
ties. Every  effort  should  ])e  made  to  provide  them  with  as  good 
growing  conditions  as  possible.  Thorough  spraying  is  essential  to 
protect  the  foliage  against  insect  and  fungous  pests,  in  order  that 
an  intelligent  reading  may  be  obtained  on  their  behavior  the  first 
season.  Seedlings  from  different  crosses  frequently  show  great 
variation  in  habit  of  growth  and  vigor  of  vine,  making  it  possible 
to  obtain  a  fairly  accurate  reading  from  the  F^  generation  (first 
year  seedlings)  of  the  value  of  different  varieties  as  parent  plants. 

Harvesting  the  Seedlings. — In  many  respects  the  harvesting 
of  the  seedlings  is  the  most  interesting  feature  of  this  work.  The 
striking  differences  that  are  met  with  in  seedlings  of  different 
parentage,  or  even  of  the  same  parentage,  are  sometimes  rather 
puzzling.  One  seedling  may  produce  rough,  uneven  tubers,  while 
the  adjoining  one  may  have  smooth  ones  (Figs.  220  and  221).  In 
like  manner,  the  shape  of  the  tuber  may  vary  in  every  conceivable 


412  POTATO  BREEDING  AND  SELECTION 

iiuuiiier;  sonic  hoing  so  knobby  as  to  be  absolutely  wortliless,  or 
so  deep-eyed  as  to  give  the  surface  of  the  tuber  an  irregular  appear- 
ance. Similarly,  all  gradations  in  color  may  be  noted.  With  the 
harvesting  of  the  seedlings  comes  the  first,  real,  selective  process 
connected  with  the  raising  of  seedling  potatoes.  All  plants  having 
irregular  tuber  progeny,  deep-eyed,  undesirable  in  color,  or  that 
are  too.  numerous,  should  be  immediately  discarded.  Only  those 
that  are  of  good  shape  should  be  retained  (Fig.  221).  Our  present 
practice  is  to  take  notes  on  the  number,  size  and  shape  of  tubers, 
frequency  and  depth  of  eyes,  color  of  skin,  and  general  desirability 


Fig.  220. — A  decidedly  unpromising  first  year  seedl 


of  the  tubers  as  a  whole.  This  information,  while  in  nowise 
exhaustive,  affords  a  basis  for  the  study  of  inheritance  of  certain 
tuber  characters,  and  may  furnish  important  data  on  the  trans- 
mission of  parental  characters.  Such  data,  if  properly  interpreted, 
enables  the  breeder  to  carry  on  his  work  witli  a  greater  degree 
of  intelligence;  and  may  even  permit  him  to  predict,  with  more 
or  less  accuracy,  what  may  be  expected  from  the  progeny  of 
certain  parents. 

As  each  selection  is  made  in  the  field,  a  number  is  assigned  to 
it  in  the  notebook.  This  number  is  also  written  on  a  string  tag, 
A^th  a  perforated,  detacliable  stub,  whicli  is  inserted  in  the  selected 
hill  and  serves  to  indicate  those  which  are  to  be  saved.  Each  selec- 
tion is  picked  up  separately  in  small  cotton  or  gunny  sacks  or  in 


HARVESTING  THE  SEEDLINGS 


413 


stout  maiiila  paper  bags,  the  stub,  with  number  affixed,  is  torn  oft' 
and  placed  in  the  bag,  while  the  string  tag  proper  serves  to  tie 
the  bag,  and  indicates  by  the  number  on  the  bag  which  seedling 
selection  it  is.  The  stub  inside  is  a  safeguard  against  the  loss  of 
the  outer  tag  or  the  number  affixed  thereto.  Usually  no  weights 
are  taken  of  first  year  seedlings,  except  in  the  case  of  extremely 
high-yielding  hills.  The  highest-yielding  seedling  thus  far  pro- 
duced by  the  writer  weighed  over  nine  and  one-half  pounds.  The 
following  year  it  has  been  our  practice  to  grow  five  plants  each  of 


Fig.  221.— a  . 


iiig  first  year  seedling. 


the  seedlings;  occasionally,  however,  when  the  seedling  seems 
unusually  promising,  ten  plants  are  grown.  Generally,  whole  tubers 
are  planted  in  order  to  insure  a  perfect  stand,  besides  effecting  a 
considerable  saving  in  time  which  would  necessarily  be  involved 
in  the  cutting  of  a  large  number  of  small  lots  of  seed.  The  five 
plants  are  sufficient  to  study  the  habit  of  growth  of  the  seedling, 
its  resistance  to  disease  and  its  tuber  development.  As  they  are 
harvested,  the  same  rigorous  selection  is  practised  as  in  the  first 
season.  From  this  period  on,  larger  plantings  are  made  of  the 
more  promising  ones  (Figs.  222  and  223).  U^]ually  it  is  not  safe 
to  introduce  a  seedling  until  it  is  five  or  six  years  old ; .  although 


414 


POTATO  BREEDING  AND  SELECTION 


there  are  exceptions  to  this  statement,  as  in  the  case  of  the  Burbank 
and  Early  Ohio,  Avhich  were  three  and  four  years  old,  respectively, 
when  first  introduced. 

The  growing  of  seedling  potatoes  on  a  large,  or  even  on  a 
moderate  scale,  is  an  expensive  proposition,  and  offers  little  com- 
pensation to  those  engaged  in  the  development  of  new  varieties. 

POTATO  IMPKOVEMENT  BY  SELECTIOX 

The  improvement  of  the  potato  by  selection  is  a  field  of  endeavor 
in  which  every  grower  interested  in  the  problem  of  increasefl 
production  per  acre  can  engage.     While,  as  has  been  previously 


1  IK  11-,   notts  „ii  Mt  llui^  ijotatoi.-,,  Pie.-,(iUL:  Lsle,  Me.,   191S.     Note  two 
Uiscastd  occtlhiD^s  111  llic  foie^round 

noted,  the  limitations  in  selection  are  much  more  restricted  than  in 
the  case  of  breeding,  in  which  sexual  reproduction  plays  an 
important  role,  it  is,  nevertheless,  by  no  means  as  limited  as  might 
be  supposed,  as  more  or  less  variation  already  exists  within  most 
of  our  cultivated  varieties. 

These  variations  express  themselves  in  a  multiplicity  of  ways, 
such  as  uniformity  in  size  and  shape  of  tuber  and  the  number 
produced  per  plant.  Some  plants  may  produce  2  or  3  large 
tubers,  others  the  same  number  of  large  tubers  but  with  a  half- 
dozen  or  more  small  ones,  while  still  others  may  be  found  producing 
from  6  to  10  or  more  medium-sized  merchantable  tubers  with  prac- 


EARLY  ATTENTION  TO  SELECTION 


415 


tically  no  small  ones.  It  is  plainly  evident  that  the  progeny  of 
such  plants  as  those  last  described  are  more  desirable  than  those 
of  the  other  two. 

In  like  manner  it  is  conceivable  that  certain  variations  may 
occur  in  the  plant  itself.  Such  variations  may  be  expressed  in  any 
of  the  following  attributes  of  the  plant  proper:  1.  Disease  resist- 


FiG.  223. — Taking  notes  on  potato  seedlings  at  Presque  Isle,  Me.,  1918.  Note  flo- 
riferous  habit  of  plants  in  central  portion  of  picture. 

ance.  2.  Drought  resistance.  3.  Heat  resistance.  4.  Greater 
vigor.  5.  Greater  adaptability  to  peculiar  environmental  conditions 
of  soil  and  climate. 

It  is  quite  possible  to  conceive  of  other  variations  which  might 
be  well  worth  considering.  It  is  the  business  of  the  selectionist 
to  detect  and  isolate  these  variations  and,  through  careful  testing, 
determine  whether  they  are  heritable  variations  transmissible  from 
one  generation  to  another,  or  whether  they  are  merely  accidental 
variations  due  to  a  larger  supply  of  moisture,  plant  food  or  some 
other  external  factor. 

Early  Attention  to  Selection. — That  the  subject  of  selection  is 
not  a  new  one,  and  that  its  possibilities  were  recognized  by  earlier 
investigators,  is  amply  substantiated  by  the  following  examples. 

In  1795,  Anderson,^  in  a  communication  to  the  potato  Com- 
mittee of  the  Board  of  Agriculture  of  Great  Britain,  suggests 
the  possibility  of  greatly  increasing  the  yield  of  potato  varieties 


416  POTATO  BREEDING  AND  SELECTION 

by  selecting  seed  from  productive  })lant.s,  and  growing  the  progeny 
of  each  selection  separately,  in  order  to  ascertain  which  was  best. 
That  he  tlioroughly  understood  the  i)rinciples  of  selection,  as  they 
are  known  today,  is  clearly  evident,  because  he  was  careful  to  sug- 
gest that  some  productive  plants  will  not  transmit  this  character 
to  their  progeny.  While  Anderson  does  not  actually  present  experi- 
mental data  to  substantiate  his  views,  he  makes  the  assertion 
that  he  can  "speak  from  experience  with  great  certainty;  and  can 
affirm  that,  by  a  careful  attention  to  these  circumstances,  a  farmer 
in  a  very  few  years  will,  in  many  cases,  more  than  double  the 
amount  of  his  average  crop  of  potatoes,  soil  and  culture  being 
the  same." 

One  of  the  earliest  experiments  that  has  come  to  notice  is  one 
which  was  carried  on  by  Hallet'^  l)etween  1868  and  1882.  His 
account  is  as  follows : 

"  In  the  case  of  the  potato,  I  have  also  applied  my  system,  startiiifr 
every  year  with  a  single  t\iber,  the  best  of  the  year  (proved  to  have  been 
so  by  its  having  been  found  to  produce  the  best  plant)  for  fourteen 
years.  My  main  object  here  has  been  absolute  freedom  from  disease,  and 
these  potatoes  are  now  descended  from  a  line  of  single  tubers,  each  the  best 
plant  of  the  year,  and  absolutely  healthy,  and  concurrently  with  the 
endeavor  to  wipe  out  all  tendency  to  disease,  I  have  always  kept  in  full 
view  the  point  of  increasing  productiveness.  The  result  may  be  thus 
shortly  stated:  Dividing  the  first  twelve  years  into  three  ■periods,  the 
average  numlier  of  tubers  upon  the  annual  best  plant  selected  was,  for  the 
first  period  of  four  years  16;  for  the  second  period  of  four  years  19;  for 
the  last  period  of  four  years  27 ;  or  nearly  double  the  number  produced 
during  the  first  series  of  four  years.  And  if,  as  I  might  very  fairly  have 
done,  I  had  confined  the  first  period  to  the  first  three  years  (instead  of 
four),  the  last  period  would  have  shown  an  average  of  27  tubers  against 
13  in  the  first  period,  or  more  than  double." 

The  evident  care  with  which  this  experiment  was  conducted, 
and  the  continued  selection  of  the  best  plant  based  on  freedom 
from  disease  and  productiveness,  would  seem  to  indicate  that  Hallet 
had  definite  clear-cut  ideas  concerning  the  advantages  of  selection 
in  building  up  vigorous  and  productive  strains. 

Observations  of  Carriere. — Carriere'*  in  discussing  variations 
in  the  potato  says: 

"  The   potato    furnished    us   with    examples    of   modifications    just    as 

remarkable  as  those  which  we  have  reported  for  beans  and  for  corn 

Every  year,  in  reality,  when  we  harvest  the  tubers  and  wish  to  conserve 
the  purity  of  the  variety,  we  are  obliged  to  purify,  that  is,  to  make  a 
choice  and  reject  those  which,  as  we  say,  have  degenerated ....  The 
modifications  in  the  potato  may  occur  equally  well  in  the  underground 
parts;    that   is   what   has   liappened    in    the   variety   called    Pousse-debout. 


FISCHER'S  WORK  417 

The  name  Pousse-debout  has  boon  j^ivon  to  this  variety  because  the  tubers 
which  it  produces,  instead  of  bein^  placed  flat  or  nearly  so  in  the  soil, 
are  arranged  one  aj^ainst  (upon)  the  other,  much  like  pieces  of  wood  are 
disposed  for  transformation  into  charcoal." 

It  is  further  stated  by  Carriere  that  the  Marjolin  potato  is  a 
variety  possessing  the  peculiar  quality  of  never  flowering,  and  of 
being  very  early;  but,  notwithstanding  this  fact,  it  is  continually 
producing  plants  which  flower  and  produce  seed,  and  which,  owing 
to  this  fact,  are  not  as  early  as  the  parent  plant.  Carriere  also 
observed  transformations  or  variations  in  color  of  flowers,  shape 
of  tubers,  and  season  of  ripening  in  the  variety  Chardon.  He 
remarks  that  these  variations  in  the  Chardon  are  rather  odd,  because 
it  had  long  been  under  his  observation  without  having  previously 
shown  an}^  variation  ■\\^hatsoever. 

Transmission  of  Productivity. — In  all  the  selection  work, 
carried  on  by  Goft'^^  in  1884  and  1885,  he  demonstrated  that  tubers 
from  productive  plants  gave  larger  yields  than  tubers  from  unpro- 
ductive plants,  the  total  gain  being  a  little  more  than  24  per  cent, 

Fischer's  Work. — In  1897  Fischer^"  began  some  selection  work 
with  the  potato  in  which  variations  in  productiveness,  shape  and 
starch  content  of  tuber,  as  well  as  habit  of  growth  of  the  plant 
were  studied.  Fischer's  work  was  very  largely  carried  on  in 
pots,  under  as  nearly  uniform  conditions  as  possible,  and  yet  the 
variations  in  the  tuber  yield  were  in  some  instances  in  the  ratio 
of  100  to  233. 

The  individual  deviation  within  the  variety  itself  was  found, 
in  the  case  of  the  Saxon  onion  potato,  to  be  associated  with  certain 
definite  characters;  for  example,  flat-round  tubers,  rich  in  starch, 
were  found  to  be  correlated  with  a  more  or  less  restricted  vegeta- 
tive growth  and  tuber  yield.  Long  tubers,  poor  in  starch,  were, 
on  the  other  hand,  found  to  be  correlated  with  strong  vegetative 
growth  and  a  high  tuber  yield,  as  compared  with  that  of  the  fla^- 
round  ones.  This  is  strikingly  illustrated  in  the  following  data, 
which  give  the  relative  proportion  of  dry  stalks  and  tubers  from  the 
two  types  of  mother  tubers : 

Strain  I.  Flat-round  mother  tubers,  rich  in  starch  ( 18.68  per  cent. )  ; 
dry  stalks  100  per  cent.,  tuber  yields  100  per  cent. 

Strain  VII.  Long  mother  tubers,  poor  in  starch  (11.83  per  cent.); 
dry  stalks  14.5,  tuber  yields  204  per  cent. 

Fischer  also  noted  the  deviations  within  these  types,  and  pre- 
sents data  showing  that,  while  a  considerable  deviation  occurred,  the 
27 


418  POTATO  BREEDING  AND  SELECTION 

maximum  yield  from  the  flat-round  type  did  not  approach  very 
closely  to  the  minimum  yield  of  the  long  type.  These  data  show 
the  following  deviations : 

Strain  II.  Flat-round  tubers,  rich  in  starch;  dry  stalks  100  per  cent; 
tuber   yield    100   per   cent. 

Strain  III.  Flat-round  tubers,  rich  in  starch;  dry  stalks  114.5  per 
cent;  tuber  yield  167  per  cent. 

Strain  V.  Long  tubers,  poor  in  starch;  dry  stalks  142  per  cent; 
tuber  yield  216.7  per  cent. 

Strain  VI.  Long  tubers,  poor  in  starch;  dry  stalks  175.5  per  cent; 
tuber  yield  233.3  per  cent. 

It  is  observed  that  the  plants  from  the  fiat-round  tubers  were 
shorter  jointed  and  matured  earlier  than  those  from  the  long 
tubers.  This  would  indicate  that  the  latter  represented  a  later 
maturing  strain. 

Productive  vs.  Unproductive  Hills. — In  December,  1904, 
Eustace*  reported  a  rather  interesting  study  on  the  behavior  of 
'•j)roductive  vs.  unproductive  hills."  When  harvesting  the  1903 
crop,  Eustace  selected  the  progeny  of  125  productive  plants  and  an 
equal  number  of  unproductive  plants.  Weights  were  taken  of  the 
tubers  from  each  of  tlie  250  plants  selected,  a  record  being  made 
of  each;  but  after  the  weights  were  taken,  no  effort  was  made  to 
keep  the  progeny  of  the  productive  hills  separate;  in  other  words, 
the  experiment  resolved  itself  into  a  mass  selection.  The  unpro- 
ductive hills  w^ere  handled  in  a  similar  manner.  In  the  following 
Spring,  10  rows  of  232  plants  each  w^ere  planted  from  the  productive 
lot,  and  5  rows  from  unproductive.  The  resultant  production  was 
at  the  rate  of  362.25  bushels  from  tbe  productive  hills  and  339.16 
bushels  per  acre  from  the  unproductive.  The  significant  feature 
of  Eustace's  data  is  to  be  found  in  the  deviation  w^hich  occurred 
))etween  the  individual  plants  in  the  1904  crop.  The  data  shows 
the  deviations  were  almost  as  great  as  in  that  of  the  original  stock 
of  the  previous  year.  The  1904  deviations  Avere  11.9  ounces  or 
39.18  per  cent  as  against  9.37  ounces  or  39.44  per  cent  in  the  1903 
crop.     In  this  connection  Eustace  says : 

"That  the  variation  was  not  materially  reduced  by  the  uniform  con- 
ditions under  which  the  experiment  was  made  was  a  surprise.  The 
conclusion  is  that  factors,  which  are  apparently  unimportant,  produce  wide 
differences  in  yield.'" 

From  our  present  knowledge  of  the  behavior  of  individual  hills 

even  though 


PRODUCTIVE  VS.  UNPRODUCTIVE  HILLS  419 

Eustace's  studies  had  been  made  with  the  progeny  of  the  individual 
hills  instead  of  in  mass  selection,  it  is  questionable  whether  the 
deviations  would  not  have  been  just  as  great  as  those  noted. 

At  the  annual  meeting  of  the  American  Breeder's  Association, 
in  1907,  Waid^*  reported  the  results  of  similar  studies  to  those  of 
Eustace.  This  work  was  conducted  at  the  Ohio  Experiment  Station 
during  the  seasons  of  1904  to  190G  inclusive.  Seed  was  selected 
from  j)roductive  and  unproductive  plants  in  the  fall  of  1903.  The 
three-year  average  from  high-  and  low-yielding  plants  was  found 
to  be  1.38  pounds  for  the  former,  and  0.73  pounds  for  the  latter, 
or  a  difference,  in  favor  of  the  high-yielding  plants,  of  over  89  per 
cent.  A  comparison  between  the  j)roductive  plants  and  those  grown 
from  the  common  or  unselected  bin-run  stock,  showed  a  gain  of 
over  25  per  cent  in  favor  of  the  productive  stock. 

The  most  interesting  feature  of  Waid's  data  is  brought  out  by 
a  comparison  of  the  average  weight  of  the  tubers  from  the  ten 
high-yielding  hills  selected  in  1903,  and  the  three-year  average 
from  these  original  hills.  The  average  of  the  ten  original  hills  was 
2.38  pounds  per  plant,  whereas  the  three-year  average  is  only 
1.38  pounds  or  a  decrease  of  almost  42  per  cent.  The  inference 
suggested  by  the  data  is  that,  in  the  selection  of  high-yielding 
hills,  one  is  not  at  all  certain  what  proportion  of  the  hills  are 
likely  to  maintain  their  seemingly  productive  character.  Eecent 
observations  regarding  the  behavior  of  high-yielding  hills  lead 
to  the  belief  that  less  real  progress  will,  as  a  general  thing,  be  made 
by  selecting  the  very  high-yielding  hills.  In  fact,  there  is  con- 
siderable evidence  accumulating  which  would  indicate  that  the 
practice  is  not  to  be  recommended.  In  this  connection.  East's'* 
statement  with  reference  to  his  experience  with  high-  and  normal- 
yielding  hills  from  a  select  strain  of  Eural  New  Yorker  No.  2 
would  seem  to  offer  supporting  evidence.  He  reports  his  obser- 
vations as  follows : 

"  In  1906  we  had  in  stock  a  supply  of  the  well-known  variety  Rural 
New  Yorker  No.  2,  which  had  heen  grown  from  a  single  hill  in  1904.  A 
selection  of  tubers  from  the  five  best-yielding  hills  was  planted  in  1907, 
and  compared  with  five  normal  hills  producing  only  one-half  as  much. 
The  five  best-yielding  hills  averaged  1.200  grams  (2  pounds  10  ounces) 
of  tubers  per  hill,  with  an  average  set  of  eight  tubers.  The  check  hills 
averaged  600  grams,  with  a  set  of  four  tubers  each.  Ten  hills  were  planted 
in  each  case,  two  tul)ers  being  planted  from  each  hill.  In  every  case, 
pieces  of  about  the  same  weight  were  planted.  The  yield  from  the  high- 
yielding  selections  was  at  the  rate  of  101  bushels  per  acre,  while  the  yield 
from  the  check  hills  was  at  the  rate  of  128  bushels  per  acre." 


420  POTATO  BREEDING  AND  SELECTION 

The  year  following,  the  progeny  from  the  high-yielding  strains 
averaged  96  bushels  per  acre,  and  that  from  the  low-yielding  90 
bushels.  In  1909  the  yields  were,  respectively,  115  and  120  bushels 
per  acre.  The  average  yield  for  the  three  seasons  Avas  at  the  rate 
of  104  bushels  per  acre  from  the  high-yielding  and  113  bushels 
from  the  low-yielding  strain. 

In  a  more  recent  article  Berthault*  summarizes  liis  obser- 
vations upon  sexual  reproduction,  which,  roughly  translated,  are 
as  follows : 

"1.  That  the  form  of  tlie  tuber  is  not  a  stable  character  in  our 
cultivated  varieties. 

2.  That  the  color,  generally  maintained  through  asexual  propagation, 
sometimes    varies. 

3.  That  the  depth  of  the  eyes,  a  character  almost  always  maintained 
in  asexual  reproduction,  also  offers,  without  apparent  cause,  examples  of 
bud  variation  " 

Selection  Methods. — While  the  ])receding  discussion  on  "pota- 
to imi)rovenient  by  selection"  has  touched,  in  a  more  or  less 
general  manner,  the  processes  of  selection  practised  by  those  Avhose 
investigations  have  been  cited,  it  has  not  dealt  with  specific  methods, 
and  their  "modus  operandi."  Since  the  publication  of  the  paper  on 
"potato  breeding  and  selection,"^"  the  views  regarding  the  impor- 
tance of  the  "tuber-unit"  as  compared  with  the  "hill  selection" 
method  of  seed  potato  improvement,  have  been  somewhat  modified, 
as  will  be  noted  in  a  subsequent  ])ortion  of  this  chapter. 

The  Tuber-Unit  Method  of  Selection. — Tbe  tuber-unit 
method  of  seed  selection  Avas  first  advocated  by  Webber^*,  in  1908, 
since  which  time  it  has  been  rather  widely  practised  by  selectionists. 
It  consists  in  planting  selected  tubers  in  such  a  way  that  the  plants 
from  each  tuber  will  be  definitely  isolated  from  each  of  the  other 
tuber-units.  The  tuber  is  cut  lengthwise,  through  its  central  axis, 
into  four  as  nearly  equal  parts  as  possible,  aiming  in  all  cases  to 
cut  through  the  cluster  of  eyes  surrounding  the  terminal  one. 
The  quarters  are  planted  consecutively,  and  a  double  space  is  left 
between  the  four  units  of  each  tuber,  in  order  that  they  may  be 
easily  distinguished  from  one  another.  In  selecting  these  tubers 
from  the  field  or  bin,  the  operator  is  supposed  to  select  only  those 
that  conform  to  the  type  of  the  variety,  that  are  free  from  all 
external  diseases,  and  that  weigh  from  5  to  9  ounces.  Smoothness 
of  tubers  and  shallowness  of  eyes  should  be  considered  when  making 
selections.     No  tubers  should  be  taken  that  show  the  least  tendency 


THE  TTTBER-UNIT  iMETHOD  OF  SELECTION  421 

to  running  out,  as  indicated  by  a  pointed  seed  or  stem-end  or  a 
constricted  centre,  usually  referred  to  as  waisted.  As  many  tubers 
should  be  selected  as  the  grower  thinks  he  can  properly  care  for 
and  make  the  necessary  observations.  Those  selected  should 
receive  the  usual  treatment  advocated  for  scab  disinfection  before 
being  planted.  While  the  original  directions  specify  that  the  tubers 
should  be  cut  into  four  equal  longitudinal  sections,  our  experience  . 
has  shown  that,  in  the  case  of  a  long  cylindrical  tuber  or  even  a 
moderately  long  tuber,  as,  for  example,  the  Early  Rose,  Early 
Ohio,  Beauty  of  Hebron  and  Burbank,  it  is  much  better  to  cut  the 
two  longitudinal  halves  crosswise  than  to  halve  them  lengthwise. 
The  reason  for  this  is  quite  apparent.  To  divide  the  halved  tuber 
lengthwise  gives  a  long,  slender  seed  piece  which  is  much  more 
likely  to  dry  out  or  deca}^,  according  as  to  whether  the  soil  is  too 
dry  or  too  wet,  while  the  seed  piece  is  germinating.  To  divide  it 
crosswise  gives  a  short,  blocky  seed  piece  which  is,  in  every  respect, 
better  fitted  to  successfully  withstand  unfavorable  soil  conditions 
after  it  is  planted.  The  claim  that  greater  uniformity  in  the  four 
seed  pieces  was  secured  by  the  longitudinal  quartering  of  the  tuber, 
has  not  been  substantiated  in  our  own  studies. 

When  the  plants  are  about  full  grown,  each  set  of  fours  should 
be  carefully  studied;  and  those  which  are  most  uniform,  vigorous 
and  healthy,  and  which  conform  most  nearly  to  the  type  of  the 
variety  should  be  marked.  Later  in  the  season  the  tuber-units 
should  again  receive  careful  study  for  the  presence  of  diseased  or 
abnormal  plants.  The  appearance  of  the  plants  at  this  time,  or 
even  at  the  earlier  period,  will  no  doubt  present  many  marked  dif- 
ferences between  the  various  units.  In  all  probability,  as  great 
variations  will  be  noted  as  those  shown  in  figures  224  to  229.  At 
harvest  time  each  unit,  that  is,  each  set  of  four  plants,  should  be  dug 
by  hand  and  the  progeny  of  each  carefully  examined.  Many  of 
those  which  were  marked  as  promising  from  the  appearance  of  the 
plants  will  be  found  undesirable  from  the  tuber  standpoint.  They 
Avill  either  have  given  a  light  yield,  or  the  tubers  will  be  found 
lacking  in  uniformity  as  regards  size  or  type,  or  both.  Select  those 
which  have  produced  a  reasonable  number  of  marketable  tubers  Avith 
a  small  proportion  of  seconds  and  culls,  and  that  are  desirable  in 
shape  and  color,  bearing  in  mind  that  the  heaviest  producing  units 
are  not  necessarily  the  most  desirable  ones  to  save.  Place  the 
tubers  from  each  unit  selected  in  separate  sacks,  and  give  each  a 


422 


POTATO  BREEDING  AND  SELECTION 


THE  TUBER-UNIT  METHOD  OF  SELECTION 


423 


Co- 


424 


POTATO  BREEDING  AND  SELECTION 


field  number.  In  labelling  the  sacks,  use  the  perforated  string  tag 
mentioned  in  the  handling  of  seedling  potatoes.  While  it  is  not 
absolutely  necessary,  it  is,  on  the  whole,  rather  desirable  to  make 
a  record  of  the  number  and  weight  of  large  and  small  tubers  pro- 
duced by  each  "unit  selected,  because  it  is  only  by  this  means  that 
one  can  really  determine  the  true  value  of  each  selection.  The 
following  season,  plant  the  progeny  of  each  unit  in  a  trial  row  by 
itself,  but  not,  necessarily,  on  the  tuber-unit  basis.  When  the 
plants  are  full  grown,  they  should  again  be  studied,  and  all  selec- 
tions which  do  not  show   a   reasonable   degree  of  uniformity   of 


Fig.  226. — A  weak  and  probably  mosaic-infected  tuber  unit  of  the  Norcross  variety, 
1911.     From  same  lot  of  seed  as  the  healthy  unit  shown  in  225. 


Fig.  227 — 1912  product  from  five  of  the  best  tubers  produced  by  the  1911  weak 
tuber  unit.     Primes  on  left,  culls  on  right. 

plants,  or  that  are  lacking  in  vigor,  or  are  diseased,  should  be 
marked  for  rejection.  A  second  examination  should  be  made 
toward  the  close  of  the  growing  season,  and  the  same  notes  made  as 
ill  tlie  preceding  inspection.  At  harvest  time,  each  progeny  row 
should  be  dug  separately,  and  only  those  which  are  productive,  and 
reasonably  uniform  in  size,  shape,  and  conformity  to  varietal  type 
should  be  saved.  From  this  period  on  it  should  be  possible  to  elimi- 
nate all  but  one  or  two  of  the  very  best  strains,  which  should 
be  groA\Ti  on  a  field  basis  the  following  year  in  order  to  increase 
the  seed   stock. 

Hill  Selection. — The  only  difl'erence  between  hill  selection  and 
the  tuber-unit  method  is,  that  in  the  one  case  a  start  is  made  with 
the  tuber  as  the  unit,  whereas  in  the  other,  the  hill  or  individual 
plant  is  the  unit.    In  hill  selection  the  growing  plants  are  carefully 


HILL  SELECTION 


425 


scanned  for  the  purpose  of  picking  those  which  are  most  promising 
from  the  standpoint  of  health,  vigor,  and  conformity  to  type  (Figs. 
23.0  to  236).     The  ideal  time  for  the  first  examination  is  when  the 


Fig.  229.— A  weak  mosaic-infected  Irish  Cobbler  tuber  unit.     From  same  lot  of  seed 
as  the  healthy  unit. 

plants  are  in  bloom,  or,  in  tlie  event  that  the  variety  does  not 
bloom,  when  the  plants  have  reached  their  full  size.  As  in  the  case 
of  the  tuber-unit  plants,  a  later  examination  should  be  made  in 
order  to  detect  diseased  or  prematurely  ripening  plants.  Just  prior 
to  harvesting  the  field,  all  the  marked  plants  should  be  dug  by 


426 


POTATO  BREEDING  AND  SELECTION 


hand  and  the  ])rogeny  of  each  carefully  examined.  The  same 
procedure  should  be  followed  from  this  point  on  as  that  outlined 
for  the  tuber-unit  work. 


Fro.  230. — A  field  of  Russef  Burbank  potatoes.     The  two  taller  plants  in  center  indi- 
cated by  the  arrows  are  "run-outs"  or  degenerate  plants.     Carbondale,  Col.     (Sweet  ranch.) 


Fig.  2.31. — Progeny  from  one  of  the  "run-outs.' 
for  seed  stock. 


These  tubers  should  never  be  used 


In  general,  the  chief  value  of  a  large  proportion  of  the  selection 
work  that  is  now  carried  on  lies  not  so  much  in  tlie  fact  that  new 
strains  have  actually  been  secured,  or  that  more  productive  strains 
have  been  developed,  but  rather  that  the  varieties  have  been  purified 
with  respect  to  varietal  mixtures,  and  to  fungous  pests  of  the  vine 


MASS  SELECTION 


427 


and  tuber.  It  is  also  due  in  some  measure  to  the  elimination  of 
the  weak,  unproductive  plants,  and  of  obscure,  physiological 
troubles.  If  the  selectionist  is  fortunate  enough  to  secure  desirable 
variations  from  the  parent  plant-  that  are  transmitted  from  one 
generation  of  tubers  to  the  other,  a  further  gain  has  been  secured. 

The  work  of  Fischer  would  indicate  that  a  high  starch  content 
is  associated  with  shape  of  tuber.  This  factor  is  one  which  the 
ordinary  man  would  be  unable  to  detect  witliout  the  aid  of  the 
chemist.  The  simpler  phases 
of  selection  work  may  be  suc- 
cessfully undertaken  by  any 
live  up-to-date  groAver  who  is 
sufficiently  interested  to  estab- 
lish a  seed  plot.  To  those  who 
do  not  care  to  practise  selection 
on  the  individual  plant  basis, 
mass  selection  offers  an  invit- 
ing field. 

Mass  Selection. — The  first 
steps  in  mass  selection  are 
identical  with  those  practised 
in  hill  selection.  The  field 
from  which  the  selections  are 
to  be  made  is  carefully  gone  over  prior  to  harvesting  the  crop; 
all  desirable  looking  plants  are  dug  by  hand  and  selections,  based 
on  the  number,  sliape,  size,  uniformity  and  quality  of  the  tubers 
produced  are  made  from  them.  At  this  point  the  processes  cease 
to  be  identical,  as  in  mass  selection  the  tubers  from  the  hundred 
or  thousand  or  more  plants  chosen  are  all  thrown  together,  and 
are  subsequently  planted  and  grown  in  much  the  same  manner 
as  the  general  run  of  seed  stock  would  be  handled.  While  mass 
selection  does  not  permit  of  building  up  or  isolating  strains  of 
a  variety,  it  does  very  largely  eliminate  the  weak,  unproductive 
and  diseased  stock.  The  advantage  of  mass  selection  over  hill 
selection  is  that  it  does  away  with,  the  necessity  of  handling  a 
large  number  of  selections  separately,  thereby  very  greatly  lessen- 
ing the  amount  of  work  connected  wdth  such  a  method  of  seed 
improvement  and  for  that  reason  will  commend  itself  to  many  a 
grower  who  could  not  be  induced  to  practise  either  of  the  two  other 
plans.  It  is  believed  that  mass  selection  is  a  step  in  the  right 
direction  and  growers  should  be  encouraged  to  adopt  it. 


Fig.  232.- 
Burbank  plant, 
lent  seed  stock. 


-Progeny  from  a  good  Russet 
These  tubers  will  make  excel- 


428  POTATO  BREEDING  AND  SELECTION 

The  Seed  Plot. — To  those  who  are  unwilling  or  unable  to  devote 
the  necessary  time  involved  in  the  practice  of  any  of  the  selection 
methods  discussed,  there  is  still  another  way  in  which  the  quality 
of  the  seed  stock  may  be  maintained  or  actually  improved.  This 
method  consists  in  planting  a  sui^cient  number  of  rows  in  the 
])otato  field  with  well-selected  seed,  and  then  going  through  them 
carefully  several  times  during  the  growing  season  for  the  purpose 
of  detecting  and  removing  any  possible  varietal  mixtures,  and  all 

the  weak  and  diseased  plants. 
When  harvested,  the  progeny 
from  these  rows  should  l)e 
stored  in  a  separate  bin  and  used 
for  planting  the  commercial 
iield  next  3'ear,  after  having 
again  selected  the  best  stock  for 
tlie  seed  plot.  The  actual  work 
involved  in  the  conduct  of  such 
a  seed  plot  is  comparatively 
slight,  while  the  increased  yields 
'-^'\-^"x-?t-i,  "v*-,^  are  relatively  large.  It  is  not 
F     ■-^'---  — Pn  "' n  ■  ir,  in  i  -n.  .1  I'u       upcessary  to  be  able  to  recognize 

set  Uurbank  plant,   but  tht-  tubtrs.'aie  nut  as       ])otato  disCaSCS  in  OrdeP  tO  main- 
uniform  in  size  and  shape  as  those  shown  in  .  ,  1       1    1.  A  n 
Fig.  232  and  will  not  make  as  good  founda-       taill    SUCh   a    Seecl   plot.       All   any 

tion  stock.  grower  needs  to  know  is  enough 

to  be  able  to  recognize  plants  that  are  not  normal  for  the  particular 
variety  grown.  If  all  abnormal  plants  are  removed,  the  chances 
are  more  than  even  that  most,  if  not  all,  of  the  diseased  plants 
will  be  removed. 

The  selectionist  should  always  maintain  a  seed  plot  in  which  to 
test  out  his  selections.  As  a  rule,  the  seed  plot  should  be  planted 
at  a  later  date  than  that  of  the  commercial  field  (Figs.  235  and 
236),  with  a  view  to  securing  somewhat  immature  and  medium- 
sized  seed  stock. 

Seed  Potato  Development  Work. — While  in  one  sense  this 
Mork  does  not  emlwdy  any  new^  ideas,  it  is  only  recently  that  any 
attempt  has  been  made  to  commercialize  the  results  secured.  It 
has  long  been  known  that  different  lots  of  seed  of  the  same  variety 
obtained  from  growers  in  various  localities  in  a  state,  or  even  in  a 
county,  show  surprisingly  wide  variations  in  yield.  Until  recently, 
no  serious  attempt  had  been  made  to  take  advantage  of  this  situ- 


SEED  POTATO  DEVELOPMENT  WORK  429 

ation  by  securing  and  disseminating  these  high-yielding  strains. 
Prof.  W.  S.  Blair,  Superintendent  of  the  Dominion  Experimental 
Farm  of  Kentville,  N.  S.,  was  one  of  the  first  investigators  to 
call  our  attention  to  this  subject,  when  he  mentioned  the  results 

of  some  studies  upon  a  number 
of  strains  or  lots  of  the  Garnet 
Chili,  Green  Mountain  and  Irish 
Cobbler  potatoes  which  he  had 
carried  on  under  the  direction 
of  W.  T.  Macoun,  the  Dominion 
Horticulturalist  of  Canada,  dur- 
ing the  years  1915  to  1917,  and 
reported  by  Macoun  in  1918.^* 
The  difference  between  the  higli- 
ost-  and  lowest-yielding  strains 
of  eight  lots  of  Garnet  Chili 
])otatoes  in  1915  was  204 
liushels.  In  191G  the  difference 
in  yield  of  the  same  stocks  was 
144  bushels;  and  in  1917  it  was 
225  bushels.  Ten  lots  of  Green 
Mountains,  tested  in  1916, 
showed  a  maximum  variation  of 
1321/2  bushels;  while  in  1917 
the  difference  was  147  bushels 
per  acre.  In  the  17  lots  of 
Irish  Cobbler,  tested  in  1916, 
there  was  a  variation  of  142 
bushels;  while  in  1917  the  dif- 
ference amounted  to  172  bushels 
per  acre. 
Fig.  234.— ProKeny  of  a  single  plant  Somc  Unreported  experimcn- 

of  the  Russet  Burbank  potato.     Mother  tu-       ,,,-,•         •       m-in  l    -in.^n    • 

ber  at  apex.      Grown  bv  the  Crystal  River      tal  StudieS  in   1919    and   1920   m 

Land  Co.,  Carbondaie.  Col.  Wisconsin  and  Minnesota  simi- 

lar to  those  conducted  at  Kentville,  Nova  Scotia,  fully  corroborate 
the  Canadian  results,  thereby  justifying  a  growing  conviction  that 
this  field  of  experimentation  offers  greater  possibilities  for  imme- 
diate results  than  does  the  tuber-unit  or  hill  selection  methods. 
The  location  of  high-yielding  strains  by  this  method  of  comparison 
as  to  the  productivity  and  general  desirability  of  given  strains 


430 


POTATO  BREEDING  AND  SELECTION 


QUESTIONS  ON  THE  TEXT  431 

enables  the  experimentor  to  immediately  place  a  goodly  quantity 
of  this  varietal  strain  in  the  hands  of  those  who  are  interested  in 
the  production  of  high  grade  seed  potatoes.  Furthermore,  it  is 
reasonable  to  assume  that  more  certain  and  lasting  results  should 
be  secured  from  the  use  of  such  a  strain  for  the  development, 
through  selective  processes,  of  a  still  more  desirable  seed  stock. 

QUESTIONS  ON  THE  TEXT 

1.  Give  the  author's  definition  of  breeding  and  selection. 

2.  What  are  the  limitations  in  breeding? 

3.  What  are  the  limitations  in  selection? 

4.  When   did   potato   breeding   begin   to   assume    importance   in    America 

and  Europe? 

5.  W^ith  the  exception  of  Goodrich,  what  was  the  chief  consideration  in 

the  minds  of  American  potato  breeders  regarding  new  varieties? 
C.  Name  some  of  the  more  prominent  of  the  nineteenth  century  American 
potato  breeders. 

7.  What  was  Goodrich's  notion  concerning  the  effect   of  long  continued 

asexual  propagation  upon   the  vigor  of   the  potato  plant? 

8.  What  remedy  did  he  propose?     What  stocks  did  he  use? 

9.  What  was  the  most  important  variety  he  produced  ? 

10.  How  many  seedlings  did  he  grow? 

11.  In  what  respect  was  Goodrich's  type  of  potato  breeding  lacking? 

12.  What  influence  did  Goodrich  exert  through  the  agency  of  the  press? 

13.  By  whom   and   at  what  date  was  the   Early   Rose   originated?     Give 

its  parentage. 

14.  What  other  varieties  did  Bresee  originate? 

15.  In    what    way    does    Pringle's    work    rise    above    that    of    most    other 

American  potato  breeders? 

16.  At  what  price  per  pound  did  Pringle  contract  to  produce  hybridized 

potato  seed? 

17.  Give  substance  of   quotation   from   Pringle's   letter   to   Fenn. 

18.  Name  some  of  the  varieties  originated  by  Brownell. 

19.  Name  some  of  Rand's  seedling  productions. 

20.  Mention  some  of  the  varieties  originated  by  Alexander. 

21.  What  varieties  did  Gleason  and  Heffron  originate? 

22.  Give  a   brief   resume   of  the   origin   of   the   Burbank   Seedling. 

23.  How   does   Burbank's   achievement   compare   with   that  of   Goodrich's? 

24.  In  what  way  did  Goodrich's  successors  profit  by  his  work  ? 

25.  What  variety  did  Alfred  Reese  produce?     Wliere  is  this  variety  most 

extensively  grown  at  present? 

26.  What    varieties    did    E.    L.    Coy    originate?      Give    parentage    of    his 

Early  Beauty  of  Hebron. 

27.  Review  the  work  of  Carman. 

28.  What  varieties  did  Bovee  produce? 

29.  What    varieties    did    Craine    give    us? 

30.  What    varieties    did    Van    Ornam    originate? 

31.  Who  was  Great   Britain's  pioneer  potato  breeder?     Review  his   work. 

32.  Review  letter  of  Robert  Fenn  to  Pringle,  -January  27,  1876. 

33.  When  did  Fenn  make  his  first  crosses  and  what  varieties  did  he  use? 


432  POTATO  BREEDING  AND  SELECTION 

34.  Give  the  parentage  of  Clark's  Magimni  Boiuini  and  some  of  the  charac- 
teristics it  possessed  which  lielped  to  make  it  famous. 

;];").  Give  the  name  of  the  variety  that  made  Archibald  Findlay  so  famous 
as  a  plant  breeder. 

36.  What   name   stands  out  most  prominently   among  the   plant   breeders 

of  France? 

37.  What    did    Wilhelm    Richter    accomplish    in    the    improvement    of    the 

potato  in  Germany? 

38.  Compare    catalogue   descriptions    of   the   new    potato    introductions    of 

the  present  period  with  those  from  1857  to  1890. 

39.  How  do  European  activities  in  potato  breeding  in  the  twentieth  century 

compare  with  those  of  the  nineteenth  century? 

40.  At  what  prices  did  early  productions  sell? 

41.  What  are  the  difficulties  confronting  the  potato  breeder  at  the  present 

time? 

42.  What   does   East   say   about   the   flowering   habits   of   our    commercial 

varieties  of  potatoes? 

43.  How   does    the   author's   opinion    compare   with    East's    deductions    on 

the  flowering  habits  of  potato  varieties? 

44.  How   do  varieties   dilTer   in   production    of   viable   pollen? 

4.").  What  was  the  character  of  the  four  American  varieties  found  to 
produce  a  dependable  supply  of  viable  pollen? 

46.  What  two  foreign  varieties  are  mentioned  as  being  good  pollen  parents? 

47.  What  assertion  did   Salaman   make  with  reference  to  male   sterility? 

48.  Describe   the   structure   of   the   pistil   and   the   stamens   of   the   potato 

flower. 

49.  W^hat   relation   between  color   of  stamens  and  development  of  pollen? 

50.  Give  relation  between  turgidity  and   male  sterility. 

51.  What  does  the  author  say  regarding  extreme  turgidity  of  the  stamens 

bordering   on   the   coriaceous? 

52.  What  should  be  the  first  and  second  steps  in  artificial  cross-pollination? 

53.  What    is   the   proper    stage    at   which    to   emasculate   potato    flowers? 

54.  Describe  method  employed  by  the  author  in  emasculation. 

55.  What    covering   is    recommended   to    inclose   the   emasculated    flowers? 

56.  What    particular    advantage    is    there    in    inclosing    foliage    with    the 

flowers  ? 

57.  What   interval   should   usually   be   allowed   between   emasculation   and 

the  application  of  pollen? 

58.  What  methods  of  collecting  and   applying  pollen  and  recording  were 

adopted  by  the  author? 

59.  How    long   does    it   usually    take    before    one    can    determine    whether 

the  cross  is  a  success  or   failure? 
GO.  When  should  the  seed  balls  be  gathered?     How  kept? 

61.  ^Vhat   is   the   simplest   method   of   removing  the   seeds   from   the   seed 

balls  or  berries? 

62.  What  directions  are  given  for  growing  seedlings? 

63.  How  long  does  it  take  good  potato  seed  to  germinate? 

64.  At  what  distance   should   the   seedlings  be   spaced   in   the  open   field? 

65.  What  notes  should  be  taken  on  each  individual  plant  when  harvesting 

and  how  should  those  saved  ))c  recorded? 

66.  How   should    the    subsequent    testing   of   the    seedlings   be   conducted? 

67.  How  many  years  should  a  seedling  usually  be  tested  before  introducing 

it?     What  exceptions  are  noted? 

68.  What  are  the  variations  sought  in   selection? 

69.  What  is  the  tuber-unit  method  of  selection? 


REFERENCES  CITED  433 

70.  What  is   the  hill   selection   method?      In    what   respect   does   it   diller 

from  the   tuber-unit   method? 

71.  What  is  meant  by  mass  selection?     How  does  it  differ  from  hill  selec- 

tion?    Is  it  a  desirable  practice? 

72.  What  other  method  of  seed  improvement  is  open  to  the  grower? 

73.  How  does  it  compare  with  the  preceding  methods? 
71.  What  is  meant  by  seed  potato  development  work? 

QUESTIONS  AND  EXERCISES   SUGGESTED  BY  THE  TEXT 

1.  What  is  the  usual   custom   of   local  growers   regarding   seed   selection 

of  potatoes? 

2.  What  improved  methods  are  tried  by  the  best? 

3.  What    results    have    been    secured    locally    from    tuber-unit    selection? 

4.  What  from   hill   selection? 

5.  When  harvesting  potatoes,  weigh  the  yields  of  some  of  the  best  and 

poorest  hills. 

6.  If  possible,  compare  the  relative  yields  in  a  hill-to-row  test. 

References  Cited 

1.  Andersox,  Jas.     1795.     On  potatoes  and  their  culture.     Report  of  the 

committee  on  the  culture  and  use  of  potatoes:  107-133,  G7-t.  Brit. 
Ed.  Agr.  Bpt.     1705. 

2.  Anonymous.     1868.     American  Agriculturist.     A  large  price  for  pota- 

toes.    27:    130,  April,   1868. 

3.  Beecher,    H.    W.      1870.      The    potato    mania.      Best's    Potato    Book 

(Utica,  N.  Y.)    1870:   1-96. 

4.  Berthault,   p.      1911.      Recherches   botaniques   sur   les   varieties    cul- 

tivees  du  Solanum  tuberosum.  Awn  8ci.  Agron.  ser.  3,  6th.  ann. 
2:    1-59,  87-143,   173-216,   248-309,   1911. 

5.  CARRiicRE,   E.   A.      1865.      Production   et   Fixation   des    Varieties   dans 

les  Yegetaux:  1-72,  Paris,  1865   (see  p.  40-41). 

6.  Dean,  Alex.     1890.     Potato  improvement  during  the  past  twenty-five 

years.     Jour.  Roy.  Hort.  Soc.     12:  45,  1890. 

7.  East,  E.   M.      1908.     Technic   of   hybridizing   the   potato.     Proc.    Soc. 

Ilort.  8ci.      (1907):   35-40,  1908. 

7a. 1910.     The   transmission   of  variations   in   the   potato   in   asexual 

reproduction.  Conn.  (New  Haven)  8ta.  Rpt.  1909-1910:  119- 
160,  1910. 

8.  Eustace,   H.    J.      190.').      An    experiment   on    the    selection    of    "seed" 

potatoes:  Productive  versus  unproductive  hills.  Proc.  Soc.  Hort. 
8ci.,  1903-1904:    60-62,   1905. 

9.  Fenn,   R.      1876.      Looking   Back.      Jour.   Hort.    d    Cottage    Gard.    8: 

99-100,  1876. 

10.  Fisher,  M.     1900.     Kartoffelzuchtungs  und  Anbauversuche.     Fuhlings 

Landw.  Ztg.  Jahrg.     49:  301-307,  343-352,  369-372,  1900. 

11.  GoFF,    E.    S.      1885-1886.      Experiments   with   tubers    from   productive 

and  unproductive  hills.  A^.  Y.  {Geneva)  Sta.  Third  Ann.  Rpt., 
1884:  301-305;  Albany.  Fourth  Ann.  Rpt.,  1885:  232-235; 
Albany,  1886. 

12.  Goodrich,  C.  E.     1857.     Raising  seedling  potatoes.     The  Horticulturist, 

12:   276,   1857. 
12a. -1863.     The  Garnet  Chili  potato.     Co.  Gent.,  22:   155,  1863. 

13.  Hallet,    F.    p.      1882.      Food    plant    improvement.      Nature,    26:    91- 

94,  1882. 
28 


434  POTATO  BREEDING  AND  SELECTION 

14.  ilACOUX,  W.  T.     1918.     The  Potato  in  Canada.     Dom.  Can.  Cent.  Exp. 

Farms  Bui.,  90:   21,  1918. 

15.  Salaman,  R.  N.     1910.     Male  sterility  in  potatoes  a  dominant  Men- 

delian    character.      Jour.    Linn.    iioc.     (London)     Bat.,    39:    301- 
302,    1910. 

15d. 1910.     The  inheritance  of  color  and  other  characters  in  potatoes. 

Jour.  Genetics,  1:   7-46,  29  pis.,   1910    (see  p.   8). 

16.  Skinner,  R.  P.     1914.     The  utilization  of  potatoes  in  Europe.     U.  /S'. 

Dept.  Com.  Spec.  Consular  Rpt.  No.  64:   1-44,  1914   (see  p.  10). 

17.  Stuart,    W.      1915.      Potato    breeding    and    selection.       IJ.    H.    Dept. 

Agr.  Bui,   176:    1-35,  May,   1915. 

18.  Waid,  C.  W.     1907.     Results  of  hill  selection  of  seed  potatoes.     Am. 

Breeders'  Ass'n.  Third  Ann.  Rpt.:    191-198,   1907. 

19.  Webber,  H.  J.     1908.     Method  of  improving  potatoes.     N.  Y.   {Cornell) 

Sta.  Bui,  251:   322-332,  1908. 

20.  Wright,  W.  P.,  and  E.  J.  Castle.     1913.     Pictorial  Practical  Potato 

Growing   (see  p.  9). 


CHAPTEE  XXII 

CLASSIFICATION  AND  DESCRIPTION  OF 
COMMERCIAL  VARIETIES 

Within  the  past  few  years  a  distinct  advance  lias  been  made 
in  the  classification  of  American  varieties  of  potatoes  into  groups 
or  classes  having  certain  distinctive  characters  of  vine  or  tuber. 
This  step  was  made  necessary  through  an  increasing  tendency  on 
the  part  of  some  seedsmen  to  give  old  varieties  new  names,  thereby 
adding  greater  confusion  to  that  which  ordinarily  obtained.  Al- 
though but  a  few  years  ha^■e  elapsed  since  the  group  classification 
was  really  undertaken  in  the  United  States,  it  has  already  exercised 
a  very  beneficial  effect  upon  the  introduction  of  new  varieties. 
In  fact,  some  of  the  seedsmen  have  modified  their  list  of  seed  potato 
offerings  so  as  to  comply  in  a  very  acceptable  manner  with  the 
classification  system. 

The  Putsche  and  Vertuch  Classification. — The  first  pub- 
lished attempt  at  classification  that  has  come  to  our  attention  is 
that  by  Putsche  and  Vertuch*  in  their  monograph  of  the  potato, 
in  which  they  present  a  classification  system  (p.  10)  which,  though 
crude,  indicates  the  desire,  even  in  those  early  days,  for  some 
method  by  which  the  varieties  could  be  grouped.  This  classification 
is  based  on  the  following  parts  of  the  plant:  (1)  plant  (number 
and  size  of  stems);  (2)  color  of  blossom;  (3)  method  of  propa- 
gation and  source  of  stock;  (4)  shape  and  form  of  the  tubers; 
(5)  smoothness  or  roughness  and  thickness  of  the  skin;  (6)  color 
of  skin;  (7)  size  of  tubers;  (8)  character  of  the  flesh;  (9)  taste 
of  the  flesh;  (10)  productiveness;  (11)  position  of  tubers  in  the 
soil;  (12)  period  of  maturity  (early  or  late).  The  authors  com- 
ment on  their  scheme  of  classification  with  reference  to  the  first 
eleven  divisions  as  follows : 

"  It  is  scarcely  necessary  to  observe  that  all  these  classifications  are 
based,  upon  variable  quantities,  which  depend  upon  soil,  position,  climate 
and  cultivation,  and  therefore  are  insufficient  for  a  complete  diagnosis. 
A  less  variable,  more  positive,  and  surer  division  is  according  to  the 
ripening   period." 

Those  ripening  between  the  first  and  middle  of  July  to  the  last 
of  August  were  classed  as  earlies,  while  those  ripening  after  the 
first  of  September  were  called  late  or  main  crop  varieties. 

435 


436  DESCRIPTION  OF  COMMERCIAL  VARIETIES 

The  explanation  given  l)y  the  authors  is  a  sufficient  criticism 
of  this  scheme  of  classification  to  make  further  comment  unneces- 
sary, as  it  must  be  evident  to  all  that  it  is  an  unworkable  one. 

Lenne's  Classification. — The  next  classification  system  that 
has  come  to  our  attention  is  that  worked  out  from  varieties  grown 
on  the  trial  field  of  the  Eoyal  State  Nursery  near  Potsdam,  in 
Prussia,  and  reported  by  Director  General  Lenne.'' 

This  classification  is  based  on  the  color  of  the  skin,  the  shape 
of  the  tuber  and  the  color  of  the  flesh.  In  this  scheme  fifteen 
combinations  or  groups  were  secured,  viz. : 

I.  Yellow-skinned,   rounded,    yellow-fleshed    varieties. 

II.  Yellow-skinned,  rounded,   white-fleshed   varieties. 

III.  Yellow-skinned,  elongated,  yellow-fleshed  varieties. 

I\'.  Yellow-skinned,   elongated,   white-flcshed   varieties. 

V.  Yellow-skinned,  kidney-shaped,   yellow-fleshed  varieties. 

VI.  Yellow-skinned,   kidney-shaped,   white-fleshed   varieties. 

\'II.  Eed-skinned,   rounded,   yellow-fleshed   varieties. 

VIII.  Red-skinned,    rounded,    white-fleshed   varieties. 

IX.  Red-skinned,  elongated,  yellow-fleshed  varieties. 

X.  Red-skinned,    elongated,    white-fleshed   varieties. 

XI.  Red-skinned,   kidney-shaped,  yellow-fleshed  varieties. 

XII.  Red-skinned,    kidney-shaped,    white-fleshed   varieties. 

XIII.  Blue-skinned,    rounded,   yellow-fleshed   varieties. 

XIV.  Blue-skinned,    rounded,    white-fleshed    varieties. 

XV.  Blaekish-blue  skinned,   rounded,  violet-fleshed   varieties. 

The  number  of  varieties  classified  under  each  of  these  fifteen 
groups  were  as  follows : 

Group  I. — 71  varieties.  Group  IX. —  ^^  varieties. 

Group  II. — 22  varieties.  Group  X.— 10  varieties. 

Group  III. — 12  varieties.  Group  XI. —  4  varieties. 

Group  IV.—  3  varieties.  Group  XII. —  1  variety. 

Group  V. —  4  varieties.  Group  XIII. —  5  varieties. 

Group  VI. —  4  varieties.  Group  XIV. —  9  varieties. 

Group  VII. — 11  varieties.  Group  XV. —  2  varieties. 

Group  ^^III. —  9  varieties. 

Vilmorin's  Classification. — The  third  classification  scheme, 
chronologically,  is  that  of  Vilmorin^^  who  in  1882,  and  again  in 
1886  and  1903,  published  the  results  of  many  years'  observations 
of  a  very  complete  collection  of  potato  varieties.  These  varieties 
were  grouped  into  13  classes  in  1886,  and  the  13  classes  were  further 
subdivided  into  30  sections.  In  the  1903  edition  only  9  classes 
were  made;  biit  these  9  classes  were  subdivided  into  40  sections. 
Vilmorin's  classification  is  considerably  more  elaborate  than  that 
of  Lenne's  previously  given,  the  classes  being  based  on  the  color 


KOHLER'S  CLASSIFICATION  437 

and  shape  of  the  tubers,  and  that  of  the  sections  on  the  color, 
shape  and  size  of  the  tubers,  the  depth  of  the  eyes,  the  color  of  the 
sprouts  in  the  dark,  and  the  color  of  the  flowers.  The  9  classes 
are  as  follows : 

1.  Yellow,   round.  4.  Flesh-colored,  oblong.    7.  Rose  or  red,  long. 

2.  Yellow,   oblong.  5.  Rose    or    red,    round.  S.  Violet-colored. 

3.  Yellow,  long.  6.  Rose  or  red,  oblong.    !).  Streaked    (mottled). 

The  varieties  included  in  class  1  are  divided  into  ten  sections, 
of  which  section  3  will  serve  as  an  illustration. 

Section  2.  Tubers,  yellow  or  white,  round;  flowers  colored, 
often  abundant ;  flesh  white ;  sprouts  violet,  more  or  less  colored, 

Kohler's  Classification. — One  of  the  first  attempts  at  group 
classification  in  the  United  States  is  that  of  Kohler,  who,  in 
March,  1909,  published  the  first  results  of  his  studies  on  the  classi- 
fication of  potato  varieties.  In  explanation  of  the  classification 
of  varieties  Kohler*  says  : 

"  Varieties  of  potatoes  may  be  classified  into  groups,  artificially,  by 
considering  the  tubers  alone,  and,  naturally,  by  considering  the  entire 
plant.  There  is  in  many  cases,  and  possibly  all,  a  definite  relation  be- 
tween type  of  tuber  and  type  of  plant,  which  means  that  the  two  methods 
of  classification  merge  into  each  other ...  .Varieties  belonging  to  closely 
related  groups  often  merge  into  each  other  and  make  it  difficult  to  draw 
the  line  between  the  groups ....  The  plan  is  to  group  together  varieties 
having  similar  plants,  and  under  these  groups  subdivide  according  to 
the  shape  of  the  tuber,  and  under  tuber  subdivide  according  to  color,  thus : 

"■  I.  Characteristics  of  vines. 

A.  Shape  of  tubers. 

B.  Color  of  tubers." 

Kohler  divided  the  varieties  in  the  collection  which  he  studied 
into  eleven  groups  as  follows : 

I.  Tuberosum.  VII.  Early  Michigan. 

II.  Rural.  VIII.  Milwaukee. 

III.  Endurance.  IX.  Russet. 

IV.  Seedling  B.  X.  Ohio. 

V.  Green  Mountain.         XI.  Early  Market. 
VI.  Carman. 

His  plan  of  subdivision  of  the  groups  can  be  best  illustrated 
by  giving  that  of  group  I. 

I.  Tuberosum. 

A.  Tubers   roundish. 

B.  Tubers  somewhat  elongated  to  about  medium  in  length. 

C.  Tubers   long. 


438  DESCRIPTION  OF  COMMERCIAL  VARIETIES 

111  a  later  publication/*  April,  1910,  Koliler  retained  the 
same  number  of  groups,  but  substituted  new  names  for  four  of 
them.  Some  change  was  also  made  in  the  order  in  which  they 
were  listed  as  will  be  noted  from  a  comparison  of  the  two  lists 
as  presented  below. 

List  I.  List  IL 

I.  Tuberosum Tnlierosum. 

II.  Rural ■  •■  •  Wohltmann. 

III.  Endurance Rural. 

IV.  Seedling   B Endurance, 

V.  Green   Mountain Factor. 

VI.  Carman Sharp's  Express. 

VII.  Early   Michigan Green  Mountain. 

VIII.  Milwaukee Michigan. 

IX.  Russet Russet. 

X.  Ohio Ohio. 

XI.  Early  Market Cobbler. 

A  careful  review  of  Kohler's  classification  studies  cannot  fail 
to  impress  the  reader  with  the  extent  of  the  work  performed ;  and, 
if  one  keeps  in  mind  the  fact  that  he  was  blazing  a  new  trail,  as 
it  were,  so  far  as  an  American  classification  was  concerned,  we 
must  concede  that  a  very  fair  beginning  was  made. 

His  work  has  been  a  source  of  helj)  to  those  who  followed  him. 

Ballou's  Classification, — Ballou's  classification,^  which  ap- 
peared about  the  same  time  as  Kohler's  second  one,  describes  seven 
groups.  The  author  explains  that  in  this  classification  he  has 
reduced  the  groups  to  the  least  possible  number,  7,  and  that  only 
a  few  of  the  many  varieties  that  might  easily  be  included  in  each 
of  the  groups  are  mentioned. 

He  further  states  that  the  classification  is  based  principally 
upon  the  similarity  of  the  character  of  the  tubers  of  the  difi'erent 
varieties,  without  s])ecial  consideration  of  the  similarity  of  the 
plants  of  each ;  but  that  in  many  cases,  however,  there  is  a  similarity 
of  plants  as  well  as  tubers.  The  seven  groups  in  Ballou's  classifi- 
cation are : 

Triumph.  Green  Mountain. 

Early  Market.  Seneca  Beauty. 

Early  Ohio.  Rural  Xew  Yorker. 
Early   Rose. 

Milward's  Classification. — In  1912,  Milward"  classified  the 
commercial  potato  varieties  of  Wisconsin  into  three  groups  which 
were  considered  to  represent  distinctive  types.     These  were  called 


STUART'S  CLASSIFICATION  439 

the  roiHid  white,  the  long  white,  and  the  rose  groups  of  potatoes. 
The  first  two  groups  are  classified  as  follows: 

Group   1.  Round  white. — 

Tubers:  Round  to  oval  and  slightly  flattened.  Surface  generally 
netted.     Skin   white,   and   flesh   white. 

Flowers:    White   or  purple. 
Group   2.  Long  white. — 

Tubers:  Long  oblong  in  shape  and  sometimes  flattened.  Skin  and 
flesh  white. 

Fitch's  Classification, — Two  years  later  Fitch-'^  descril)e(l 
seven  groups  of  American  varieties  of  potatoes,  viz.,  the  Eural,  Early 
Ohio,  Irish  Cobbler,  Green  Mountain,  Burbank,  Peerless  or  Pearl, 
and  Bliss  Triumph.  The  description  of  each  of  these  groups 
is  good,  and  is  well  worth  the  careful  study  of  those  interested 
in  the  characteristic  appearance  of  the  members  of  each  of  them. 
Photographs  representing  the  range  of  variation  in  tuber  shape 
within  each  group  enable  the  student  to  acquire  a  fairly  good  con- 
ception of  the  range  of  variation  in  the  form  of  the  tubers. 

Kranz's  Flower-stalk  Classification. — Kranz^  has  recently 
suggested  another  character  for  potato  identification,  viz.,  the 
position  of  the  flower  stalk.  lie  found  that  in  the  Irish  Cobbler, 
Early  Eose,  and  Early  Ohio  the  flower  stalks  are  borne  in  the 
axil  formed  by  a  leaf  and  the  main  stalk.  The  Triumph,  Burbank 
and  Green  Mountain  bear  their  flower  stalks  on  the  petiole  of  the 
leaf.  In  the  Eural  group  the  flower  stalks  are  borne  on  the  main 
stem,  usually  at  a  slight  distance  from  the  axil  of  the  leaf. 

Snell's  Classification. — This  classification,  published  in  1931,'^ 
is  based  on  date  of  ripening,  color  of  tubers,  and  plant,  stem,  leaf 
and  flower  characters.  The  main  classification,  however,  is  based 
on  the  first  two  characters.  The  author  divides  German  potato 
varieties  into  two  classes  or  sections : 

I.  Early  or  medium  early. 
II.  Late  or  medium  late. 

Four  groups  of  potatoes  are  assigned  to  the  first  division,  while 
the  late  or  medium  late  varieties  are  subdivided  into  two  sections : 
(a)  those  with  white  or  blue  tubers,  and  (b)  those  with  red  tubers. 
The  first  subdivision  includes  three  groups  and  the  second  two. 

The  description  of  the  tubers  in  each  of  these  groups  is  greatly 
facilitated  by  a  colored  plate.  The  flower  and  sprout  characters 
are  shown  on  plate  3. 

Stuart's  Classification.— In  March,  1915,  Stuart^^^  published 
a   system   of   classification   somewhat   similar  to   that   of   Fitch's, 


440  DESCRIPTION  OF  COMMERCIAL  VARIETIES 

although  the  latter's  bulletin  did  not  come  to  his  attention  until 
page  proof  of  bulletin  176  was  being  corrected,  when  a  footnote 
was  inserted,  mentioning  the  Iowa  publication.  In  this  classifi- 
cation eleven  groups  are  recognized.  These  were  based  on  studies 
extending  over  a  period  of  ten  years,  in  which  the  author  had  an 
opportunity  to  study  the  behavior  of  varieties  from  Maine  to 
California  and  from  New  Jersey  to  Florida.  In  dis(;ussing  his 
proposed  S3'stem  of  classification  he  says  (p.  3)  : 

"  In  presenting  the  following  classification  key  and  group  description, 
no  one  realizes  more  clearly  than  does  the  writer  that  there  is  still  much 
to  be  desired.  It  is  hoped,  however,  that  this  classification  will  serve  as 
a  starting  point  upon  which  to  base  further  studies.  It  is  quite  probalile 
that  the  groups  here  presented  will,  in  many  cases,  resolve  themselves  into 
one  or  more  sub-groups  or  sections  which  are  based  on  finer  distinctions 
than  those  given  for  the  group  as  a  whole.  It  is  equally  certain  that  some 
new  groups  will  have  to  be  made  in  order  to  include  those  varieties 
which  do  not,  at  present,  seem  to  fit  into  any  of  the  classes  now  proposed." 

"  The  value  of  stiidying  varietal  groups  cannot  be  too  strongly 
emphasized.  When  the  varieties  fitting  into  such  groups  are  planted  in 
adjacent  rows  the  comparative  differences,  as  well  as  similarities,  are  more 
easily  noted.  The  recognition  of  old  varieties  xmder  new  names  is  almost 
certain  to  result  from  such  a  study,  and  should  tend  to  discourage  the 
present  practice  of  some  of  the  seedsmen  who  manufacture  new  varieties 
out  of  old  ones." 

The  following  classification  key  has  been  found  very  helpful 
in  studying  potato  varieties.  It  is  not  an  exact  reproduction  of 
bulletin  176,  some  minor  changes  having  l)een  thought  desirable. 
In  all  other  respects  the  two  keys  are  identical. 

Classification  Key   (Stuart's) 

(The  color  values  are  based  upon  the  chart  puldished  by  the  French 
Chrysanthemum  Society,  Paris,  1905). 

Group   1.  Cobbler. — 

Tubers:  Roundish  to  roundish-flattened  or  slightly  oblong,  stem-end 
usiially  deeply  recessed  or  notched;   skin  creamy -white.      (Plate  I-A). 

Sprouts:  Base,  leaf  scales  and  tips  slightly  or  distinctly  tinged  with 
roddish-violet  or  magenta.  In  some  cases  the  color  is  nearly,  if  not  entirely, 
absent.      (Plate  I-A). 

Flowers:  Light  rose-purple,  under  intense  heat  may  be  almost  white. 
Plants  flower  very  profusely  in  some  sections.      (Plate  I-A'). 

Group  2.  Triumph. — 

Tubers:  Eoundish  to  roundish-fiattened ;  skin  solid  red  or  magenta 
in  the  case  of  the  Triumph  to  creamy-white  with  more  or  less  numerous 
splashes  of  red  or  carmine  in  the  case  of  Noroton  Beauty;  and  white  with 
faint  to  pronounced  coloring  in  the  eyes  in  the  case  of  White  Triumph; 
maturing  early.      (Plate  I-B). 

Sprouts:  Base,  leaf  scales  and  tips  more  or  less  deeplv  suffused 
with  reddish-violet.    (Plate  I-B). 


PLATE  I. 

A — Tuber  of  the  Irish  Cobbler  showing  color  of  skin  and  of  sprout. 

A'— Flower  truss  of  the  Irish  Cobbler  showing  size  and  color  of  buds  and  ex- 
panded blossoms. 

B — Tuber  of  the  Triumph  variety  showing  typical  appearance  of  the  skin 
and  sprouts. 

B' — A  typical  flower  cluster  of  the  Triumph  showing  paucity  of  individual 
flowers  and  evidences  of  premature  dehiscence,  or  dropping  off  of  bloom. 

C — A  typical  tuber  of  the  Pearl  variety.  Note  deep  stem -end  recession  and 
heavy  shouldering  of  tuber. 

C' — A  flower  truss  of  the  Pearl.  True-to-type  Pearls  seldom  show  more  than 
two  to  three  expanded  flowers  in  any  one  cluster  and  always  present 
evidence  of  the  premature  dropping  of  flower  buds  before  opening. 


PLATE  II. 

D — A  representative  Early  Rose  tuber  showing  skin  and  sprout  characters. 

D' — An  average  flower  truss  of  the  Early  Rose.    Note  profusion  of  bloom. 

E — A  well  shaped  Early  Ohio  tuber  showing  characteristic  skin  and  sprout 
coloration. 

E' — An  average  flower  truss  of  the  Early  Ohio.    Note  paucity  of  bloom  and 
light  color  of  stamens. 

F — A  desirably  shaped  Beauty  of  Hebron  tuber.    Note  unevenness  of  skin 
coloration  and  creamy  white  appearance  of  skin  surrounding  the  eyes. 

F' — A  flower  truss  of  the  Beauty  of  Hebron.  Note  intermediate  stage  between 
Early  Rose  and  Early  Ohio  in  number  of  blooms. 


STUART'S  CLASSIFICATION  KEY  441 

Flowers:  Very  light  rose-purple,  rather  small,  flowers  sparingly. 
(Plate  I-B'). 

Group  3.  Early  Michigan. — 

Tubers:  Oblong  or  elongate-flattened;  skin  white  or  creamy-white, 
occasionally  suffused   with  pink  around  bud-eye  cluster  in   Early   Albino. 

Sprouts:  Base  light  rose-purple;  tips  creamy-white  or  light  rose-purple. 

Flowers:  White,  rather  profuse. 

Group  4.  Rose. — 

Tubers:  Elongate-flattened  to  spindle-shaped  flattened  in  section  1,  or 
oblong-flattened  in  the  case  of  section  2;  skin  flesh-colored  or  pink;  bud- 
eye  cluster  deep  magenta,  (Plate  II-D)  ;  in  the  case  of  the  White  Rose 
the  skin  is  white. 

Sprouts:  Base  and  internodes  creamy-white  to  deep  rose-lilac;  leaf 
scales  and  tips  cream  to  rose-lilac.      (Plate  II-D). 

Flowers:    White;    blooms    fairly    abundant.       (Plate    II-D'). 

Group  5.  Earli/  Ohio. — 

Tubers:  Round-oblong,  or  ovoid,  generally  slightly  flattened  though 
not  always;  skin  flesh-colored  or  light  pink,  usually  with  numerous 
medium-sized,  rather  conspicuous  russet  dots  or  lenticels.      (Plate   II-E). 

Sprouts:  Base,  leaf  scales  and  tips  more  or  less  deeply  suffused  with 
carmine-lilac,  to  violet-lilac  or  magenta.     (Plate  II-E). 

Flowers:   White;    moderate  bloomer.      (Plate   II-E'). 

Group  6.  Hebron. — 

Tubers:  Elongated,  and  distinctly  flattened,  sometimes  spindle-shaped; 
skin  creamy-white,  more  or  less  colored  with  flesh  color,  or  light  pink. 
Creamy-yellow  around  eyes.     (Plate  II-F). 

Sprouts:  Base  creamy-white  to  light  lilac;  leaf  scales  and  tips  pure 
nuiuve  to  magenta,   color   often   absent.    (Plate   II-F). 

Flowers:    White;   moderately  free  bloomer.    (Plate  II-F'). 

Group   7.  Biirbank. — 

Tubers:  Long,  cylindrical  to  distinctly  flattened,  inclined  to  be 
somewhat  spindle-shaped;  skin  white  to  creamy-white  (Plate  III-G), 
smooth  and  glistening  or  slightly  netted,  or  deeply  netted  and  dark,  russet 
in  the  case  of  section  2.      (Plate  III-G'). 

Sprouts:  Base  creamy-white  or  faintly  tinged  with  magenta;  leaf 
scales  and  tips  usually  lightly  tinged  with  magenta  but  quite  often  color 
is  absent.   (Plate  III-G  and  G' ) . 

Flowers:    White,   moderate   bloomer.      (Plate   III-G"). 

Group  8.  Green  Mountain. — 

Tubers:  Moderately  to  distinctly  oblong,  usually  broad,  flattened  with 
blunt  ends;  skin  a  dull  creamy  or  light  russet  color;  sometimes  rather 
heavily  netted  especially  toward  the  seed  end.     (Plate  III-H). 

Sprouts:  Section  1. — base,  leaf  scales  and  tips  creamy -white.  (Plate 
III-H)  ;  section  2. — base  usually  white,  occasionally  tinged  with  magenta; 
leaf  scales  and  tips  tinged  with  lilac  to  magenta;  usually  color  is 
very   faint. 

Flowers:    White;   blooms  profusely.      (Plate   III-H'). 

Group  9.  Rural. — 

Tubers:  Broadly  round-flattened  to  short  oblong,  or  distinctly  oblong- 
flattened;  skin  creamy-white,  usually  smooth,  but  sometimes  lightly  netted; 
or  heavily  netted,  and  russet  color  as  in  section  2.      (Plate  III-I  and  I'). 

Sprouts:  Base  dull  white;  leaf  scales  and  tips  violet-purple  to  pansy- 
violet.      (Plate  III-I). 


442  DESCRIPTION  OF  COMMERCIAL  VARIETIES 

Flowers:  Central  portion  of  corolla  deep  violet-purple  with  the  color 
growing  lighter  toward,  the  outer  portion ;  five  points  of  corolla  white 
or  nearly  so.     Moderate  bloomer.      (Plate   III-I" ) . 

Group    10.  Pearl. — 

Tubers:  Round-flattened  to  heart-shape  flattened,  itsually  heavily 
shouldered  due  to  deep  recession  of  stem;  skin  dull  white  or  buff  in 
section  1,  (Plate  I-C),  distinctly  russet  or  brownish  color  in  section  2, 
or  a  deep  bluish-purple  with  occasional  creamy-white  splashes,  usually 
around  the  eyes  in  section  3. 

Sprouts :  Sections  1  and  2. — base,  leaf  scales  and  tips  usually  faintly 
tinged  with  lilac,  (Plate  I-C);  section  3. — base,  leaf  scales  and  tips 
vinous-mauve. 

Flowers:    White;   blooms  very  sparingly.      (Plate   I-C). 

Group    11.  Peachbloic. — 

Tubers:  Round  to  round-flattened  or  round-oblong;  skin  creamy-white, 
splashed  with  crimson  or  solid  pink;  eyes  bright  carmine.  Includes  some 
early-maturing  varieties.      ( Plate  IV- J, J'  and  K ) . 

Sprouts:  Base,  leaf  scales  and  tips  more  or  less  suffused  with  reddish- 
violet.      (Plate  IV- J  and  K). 

Flowers :  Purple,  usually  rather  free  bloomers.     ( Plate  IV-J"  and  K' ) . 

Group   12.   Up-to-Date. — 

Tubers:  Oblong-flattened  to  somewhat  obovate-flattened ;  skin  creamy- 
white,  moderately  netted  or  nearly  smooth.      ( Plate  IV-L  ) . 

Sprouts:  Base  dull  white,  leaf  scales  faintlv  to  distinctly  tinged 
with  light  magenta.      (Plate  IV-L). 

Flowers:  Rose-purple;  moderate  to  fairly  profuse  bloomer.  (Plate 
IV-L' ) . 

Pistil:    Usually  short,  thick  and  curved  with  enlarged   stigma. 

The  last  group  (12)  has  been  added  to  accommodate  a  few 
varieties  of  Scotch-Englisli  origin  which  are  being  grown  to  some 
extent  in  the  United  States  and  to  a  greater  degree  in  Canada,  and 
from  which  there  seems  to  be  springing  up,  or  emanating,  certain 
varieties  presumably  of  American  origin  which  have  been  more  or 
less  widely  disseminated.  Whether  these  varieties  are  simply  the 
Up-to-Date  or  Factor  re-named  is  difficult  to  determine,  but  in  any 
event  they  must  be  considered  members  of  a  group  which,  in  certain 
sections  of  the  New  World,  may  become  the  leading  commercial 
type  of  potatoes  grown. 

In  regard  to  the  naming  and  describing  of  the  groups  the 
bulletin  says  {I.e.  p.  5)  : 

"In  deciding  upon  the  name  by  which  each  group  shall  be  known,  an 
attempt  has  been  made  to  select  that  of  the  variety  which  seems  most 
nearly  to  represent  the  group  as  a  whole  and  which,  at  the  same  time, 
is  most  widely  known." 

The  classification  key  presented  is  too  brief  to  do  other  than 
to  serve  as  a  simple  means  of  placing  a  variety  in  the  group  to 
which  it  seems  related.  The  more  complete  description,  which 
follows^  is  in  a  large  measure  a  reproduction  of  that  published  by 


PLATE  III. 

G — A  well  shaped  tuber  of  the  Burbank  variety  showing  skin  and  sprout 
coloration. 

G'— A  fair  specimen  tuber  of  the  Russet  Buibank.  Note  deep  russet  color 
and  heavy  netting  of  skin. 

G" — Flower  truss  of  the  Burbank  potato.  Note  length  ol  petals  of  unopened 
buds  and  hght  color  of  stamens. 

H — A  good  specimen  tuber  of  the  Green  Mountain  variety. 

H' — A  small  flower  truss  of  the  Green  Mountain  potato.  Note  deep  orange- 
yellow  color  of  stamens.  Compare  shape  of  unopened  buds  with  those  of 
the  Burbank. 

I— A  show  tuber  of  the  Rural  New  Yorker  No.  2  (Rural  Group).  Note  shal- 
low eyes  and  violet  color  of  tips  of  sprouts  and  leaf  scales. 

I' — A  good  specimen  of  the  Russet  Rural  potato. 

I" — A  typical  flower  truss  of  the  Rural  Group  of  potatoes.  Note  color  of 
petals  of  unopened  buds  and  of  corolla  of  expanded  flower. 

I'" — A  portion  of  the  stem  of  a  Rural  New  Yorker  No.  2  plant  showing 
coloration  of  the  epidermis. 


PLATE  IV. 

J — A  McCormick  tuber  somewhat  better  than  the  average  shape,  showing 
normal  skin  and  sprout  coloration. 

J'— A  fair  tuber  specimen  of  the  White  McCormick.    Note  absence  of  color 
in  skin  and  sprouts. 

J" — An  average-sized  flower  truss  of  the  McCormick  variety. 

K — A  good  specimen  tuber  of  the  Perfect  Peachblow  (Red  McClure)  variety. 

K' — Flower  truss  of  the  Perfect  Peachblow. 

L — A  representative  tuber  of  the  Up- to- Date  variety  of  potato.     Note  shal- 
lowness of  eyes  and  coloration  of  sprouts. 

L'— Flower  truss  of  the  Up-to-Date  variety.     Note  similarity  of  color  of 
unopened  buds  to  that  of  the  McCormick. 


DESCRIPTION  OF  GROUPS 


443 


Stuart  {I.e.  p.  5).  Such  changes  as  occur  are  the  result  of  a  more 
intimate  knowledge  of  the  group  as  a  whole  and  the  type  variety 
in  particular. 

Description   of   Groups.      Group    i. — The    Cobbler   group 

represents  a  class  of  early-maturing  potatoes.     The  Irish  Cobbler 


C  D 

Fig.  237. — Four  views  of  a  well-shaped  though  rather  shallow-eyed  Irish  Cobbler  tu- 
ber.   A — upper:  B — lower;  C — seed  end;  D — stem  end  view. 

is  by  far  the  most  extensively  grown  variety  of  this  group.  It  is 
now,  and  has  been  for  a  number  of  years  past,  the  leading  com- 
mercial early  market  variety  in  the  Atlantic  Coastal  Plain  region 
from  Long  Island  to  Georgia.     It  is  also  grown  extensively  in  the 


444  DESCRIPTION  OF  COMMERCIAL  VARIETIES 

Louisville,  Kentucky,  district.  Large  quantities  of  Irish  Coljljler 
are  also  grown  in  some  of  the  late  or  main-crop  producing  sections 
of  the  North,  notably  of  northern  Maine  and  New  York  and  ni 
certain  localities  in  Michigan,  Wisconsin  and  Minnesota.  In  the 
northern  sections  it  is  principally  grown  for  the  purpose  of  sup- 
plying seed  to  the  southern  truck  grower.  Figures  237  and  238,  and 
n.  1-A  illustrate  different  types  of  potatoes  belonging  to  group  1. 
Description. — Matures  early.  Vines  medium  to  above  medium 
in  size  with  somewhat  spreading  habit  of  growth.  Stems  dark 
green,  stocky  and  rather  short-jointed.    Leaves  large,  flat  or  nearly 


'|g(r 


t 


Fig.  238. — Two  representative  Irish  Cobbler  tubers  showing  averatie  depth  ot  bud  eyes. 

SO,  more  or  less  flaccid  in  northern  Maine  when  grown  under 
optimum  conditions,  but  much  smaller,  as  a  rule,  in  the  Central 
West;  they  are  medium  dark  green  in  color.  Flowers  numerous, 
rather  large,  light  puriDle-  or  rose-lilac ;  under  intense  heat  the  color 
may  be  practically  unexpressed.  Tubers  roundish  to  roundish- 
flattened  or  slightly  oblong-flattened,  the  stem-end  usually  rather 
deeply  notched  giving  a  rather  shouldered  appearance  to  the  base 
of  the  tuber  (PI.  1-13).  Eyes  medium  in  number,  varying  from 
shallow  to  rather  deep,  particularly  in  the  bud-eye  cluster,  (PL  II). 
Skin  usually  smooth,  but  sometimes  fairly  well  netted,  as  in  the 
case  of  the  Potentate,  light  creamy-wliite  in  color.  Sprouts  stout 
and  rather  stubby,  vary  in  color  at  the  base  from  a  very  faint 
reddish-violet  or  magenta  to  a  perceptible  coloration;  tlie  tips  and 
leaf  scales  are  usually  tinged  with  the  same  color.  Occasionally 
the  color  is  almost,  if  not  entirely,  absent. 


GROUP  2.   TRIUMPH 


445 


The  following  varieties  have  been  classed  in  the  Cobbler  grouj)  and, 
to  all  intents  and  purposes,  most  of  them  are  identical. 

Early  Beauty. 
Early  Dixie. 
Early  Eureka. 


Early  Petoskey. 
Early  Standard. 
Early  Victor. 
Early  Waubonsie  * 
Extra  Early  Eureka. 

Group  2.  Triumph. — This  group  includes  the  earliest  named 
varieties  grown  in  the  United  States.  The  Triumph  is  the  leading 
commercial  variety  of  the  group,  as  well  as  its  oldest  memher.     It 


First  Early. 
Flourball. 
Happy  Medium. 
Irish  Cobbler. 
Irish  Daisy. 
New  White  Victor. 
Potentate. 
Trust  Buster.* 


Fig.  239. — A  well-shaped  and  good  type  Triumph  tuber  natural  size. 

is  chiefly  grown  in  the  States  of  Florida  (southern  part),  Alabama, 
Mississippi,  Louisiana,  Texas,  Oklahoma,  Arkansas  and  portions 
of  Tennessee,  in  which  sections  it  is  the  leading  truck  crop  variety. 
In  the  North,  it  is  grown  most  extensively  in  Maine,  Wisconsin, 
Minnesota  and  Nebraska,  in  order  to  supply  the  southern  grower 
with  seed  stock.  Ordinarily  it  is  not  grown  in  the  North  primarily 
for  table  stock. 

Description. — Very    early.      Vines    medium    to    small,    fairly 

compact,  not  much  branched.     Stems  short,   stocky,  dark  green. 

*  Classified  by  Prof.  A.  L.  Dacy,  Exp.   Station,  Morgantown,  W.  Va. 


446 


DESCRIPTION  OF  COMMERCIAL  VARIETIES 


U**^.,  > 


GROUP  2.   TRIUMPH 


447 


448  DESCRIPTION  OF  COMMERCIAL  VARIETIES 

Flowers  usually  fevv'  in  number,  small  in  size,  and  of  a  rose-lilac 
color.  Tubers  roundish  to  roundish-flattened  with  stem-end  slightly 
to  distinctly  shouldered  (Figs.  239  to  241  and  PL  I-B).  Eyes 
medium  in  number,  rather  shallow ;  bud-eye  cluster  generally  more 
or  less  depressed.  Skin  creamy-white,  generally  with  pink  eyes,  and 
occasionally  with  splashes. — White  Triumph. — with  few  or  many 
splashes  of  crimson  as  in  the  Quick  Lunch  and  Noroton  Beauty; 
or  solid  red,  or  occasionally  solid  red  splashed  with  crimson,  as  in 
the  Triumph.  Flesh  a  creamy-white.  Sprouts  have  base,  leaf 
scales  and  tips  more  or  less  deeply  suffused  with  reddish-violet. 
The  varieties  assigned  to  the  Early  Michigan  group  are  as   follows: 

Early  Prospect.  Quick  Lunch. 

Honeoye  Rose.  Triumph  (Bliss's). 

Noroton  Beauty.  White  Triumph. 

Wood's  Earliest. 

Of  the  above  list  of  names  Early  Prospect  is  perhaps  the  most 
flagrant  example  of  a  recent  occurrence  of  the  re-naming  of  an 
old  and  easily  recognized  standard  commercial  variety,  as  it  is  a 
simon-pure  Trium})h.  Honeoye  Rose,  Noroton  Beauty,  Quick 
Lunch  and  Wood's  Earliest  are  identical.  The  varieties  of  this 
group  seem  to  be  peculiarly  susceptible  to  the  mosaic  disease. 

Group  3. — The  Early  Michigan  group  has  been  provided  for 
the  purpose  of  accommodating  certain  early-maturing  white-skimied 
varieties  which,  owing  to  the  character  of  their  vine  growth,  color 
of  flowers,  and  color  and  shape  of  tubers  do  not  fit  into  either 
of  the  two  preceding  groups  or  of  any  of  the  succeeding  ones.  The 
members  of  this  group  are  most  closely  related  to  the  Green  Moun- 
tain class  of  potatoes.  Commercially  speaking,  they  are  not  very 
extensively  grown  but  apparently  have  a  place  in  certain  localities 
in  the  Middle  West  as,  for  example,  around  Chicago  and  Detroit. 
Description. — Medium  early  to  mid-season.  Vines  of  medium 
size.  Flowers  fairly  abundant,  medium  size,  white.  Tubers  oblong- 
flattened  to  elongate-flattened  or  ovoid  (Figs.  242  and  243). 
Eyes  numerous,  medium  size  and  depth.  Skin  white  or  creamy- 
white  or,  in  the  case  of  the  Early  x4.1bino,  occasionally  suffused  with 
pink  around  the  bud-eye  cluster.  Sprouts  light  rose-purple  at 
the  base,  with  the  scales  and  tips  creamy-white  or  tinged  with 
light  rose-purple. 

The  varieties  assigned  to  the  Early  Micliigan  group  are  as   follows: 

Dew  Drop.  Early  Puritan. 

Early  Albino.  Ehnola. 

Early  Harvest.  E.xtra  Early  Sunlight. 

Early  Michigan. 


GROUP  3.— THE  EARLY  MICHIGAN 


449 


29 


i50 


DESCRIPTION  OF  COMMERCIAL  VARIETIES 


Group  4.  Rose. — In  point  of  numbers,  the  Eose  group  is  one  of 
the  largest.  With  the  exception  of  the  Extra  Early  White  Eose, 
all  of  the  varieties  in  this  group  have  pink  or  flesh-colored  tubers 
and  all,  save  the  late  Eose,  may  be  classed  as  early  or  mid-season 
varieties.  The  Early  Eose  is  perhaps  more  widely  grown  than  any 
other  variety,  outside  possibly  of  the  Early  Ohio;  but  neither  it 
nor  the  group  as  a  whole  can  be  regarded  as  an  important  com- 
mercial factor  in  the  potato  industry  of  this  country,  because  in 


>| 


Fio.  244. — Tuber  on  left  reproduced  from  one  of  the  original  cuts  used  to  illustrate 
the  Early  Rose  variety,  Group  4.  Note  prominence  of  the  eyes.    Right  from  the  photograph. 

no  locality  except  Florida  are  they  extensively  grown  at  the  present 
time.  However,  the  group  is  an  interesting  one,  as  the  Early  Eose, 
in  a  sense,  represents  the  fountain-head,  as  it  were,  of  many  of 
our  present  day  varieties  belonging  to  other  groups. 

In  order  to  include  certain  varieties,  which  apparently  belong 
to  this  group,  but  which  differ  somewhat  in  growth  of  plant,  shape 
of  tuber,  and  color  of  skin  and  sprouts,  it  has  been  found  necessary 
to  make  two  sections,  to  the  first  of  which  are  assigned  the  true 
Early  Eose  types.  In  this  connection  it  is  desired  to  call  attention 
to  the  fact  that  in  Department  Bulletin  176,  previously  referred 


GROUP  4.  ROSE 


451 


to,  a  third  section  was  provided  in  this  group,  in  order  to  include 
certain  varieties  which  possess  some  of  the  Early  Rose  attributes, 
but  which  difl:ered  in  color  of  bloom,  and  shape  and  color  of  tuber 
to  such  an  extent  that  it  has  been  decided  to  omit  them  entirely 
in  the  present  classification.  The  comparative  unimportance  of 
the  varieties,  from  a  commercial  standpoint,  is  also  another  con- 
sideration in  leaving  them  out. 

In  the  description  that  follows,  an  attempt  is  made  to  cover 
the  Early  Rose  proper,  and  to  note 
such  departures  from  it  as  may  occur 
m  varieties  belonging  to  section  3. 

Description. — Section  1.  Vines  of 
medium  height,  with  stout,  rather 
erect,  dark  green  stems  and  medium 
to  large  leaves.  Flowers  rather 
abundant,  white.  Tubers  elongate- 
iiattened  to  spindle-shape  flattened 
(Figs.  244  and  245,  and  Fl.  II-D). 
Eyes  numerous  and  well  distributed, 
shallow  to  medium  in  depth,  some- 
times protuberant  (Fig.  244).  Skin 
smooth  and,  except  in  the  White 
Rose,  of  a  rather  deeper  shade  of 
flesh  color  than  Early  Ohio ;  the  seed 
end  usually  a  deep  pink.  In  some 
types  of  soil,  and  in  some  regions, 
the  color  of  the  skin  is  very  much 
intensified.  Flesh  creamy-white, 
sometimes  streaked  with  red  or  pink. 
Sprouts  rather  long,  medium  thick,  the  base  not  much  enlarged 
and  usually  clearly  tinted  with  rose-lilac;  leaf  scales  and  tips 
creamy-white  or  tinged  with  rose  lilac  (Plate  2-D). 

The  following  varieties  have  been  classed  in  section  1 : 


Fig.  245. — A  well-shaped  Early 
Rose  tuber,  but  it  is  not  typical  of  the 
variety. 


Clark's  No.  1. 
Early  Durham. 
Earlj'  Fortune. 
Early  Maine. 
Early  Rose. 
Early  Sunrise. 


Extra  Early  Fillbasket. 
Extra  Early  Vermont. 
Houlton  Rose. 
Late  Rose. 
Northern  Beautj\ 
Rochester  Rose. 


Early  Thoroughbred.     Somer's  Extra  Early. 
Early  Vermont.  Thorburn. 


Early  Walters. 


White  Rose  (Extra  Early  and  Woodbury's). 


452  DESCRIPTION  OF  COMMERCL\L  VARIETIES 

Section  2. — Vines  larger  and  more  luxuriant  than  those  of 
section  1.  Flowers  rather  abundant,  but  not  opening  as  freely  as 
in  section  1.  Tubers  broad-roundish  flattened  to  oblong-flattened, 
with  rather  blunt  ends  in  the  case  of  the  King.  Eyes  not  so 
numerous  as  in  section  1 ;  medium^  shallow  except  in  overgrown 


Fig.  246. — A  good  specimen  of  a  spaulding  No.  4  tuber  grown  at  Hastings  Florida. 

specimens.  Skin  slightly  deeper  colored  than  that  of  the  Early 
Rose.  Sprouts  shorter  and  thicker  and  usually  enlarged  at  the 
base;  color  of  sprouts  mauve;  loaf  scales  and  tips  deep  mauve 
or  magenta. 

The  varieties  classed  under  section  2  are: 
King. 

Manistee     (Early    and    Improved). 
Spaulding  No  4.    (Rose  41. 

Group  5.  Early  Ohio. — Tii  many  res])ects  the  members  of  the 
Early  Oliio  group  are  very  similar  to  those  of  the  Rose,  but  inas- 


GROUP  rx  EARLY  OHIO 


453 


much  as  it  is  so  well  known,  and  is  so  extensively  grown  commer- 
cially, it  seems  desirable  to  retain  the  Early  Ohio  varieties  in  a 
distinct  group,  rather  than  to  merge  them  with  the  Kose  varieties. 
The  Early  Ohio  varieties,  with  the  ex(!eption  of  the  Late  Ohio, 


Flan.  247.  AND  248.— A   good  specimen  of  Early  Ohio  as  produced   iu  Mail 
shortened  longitudinal  axis  and  increased  transverse  diameter. 


Fig.  249. — An  excellent  specimen  of  Early  Ohio  from  the  Middle  West.  Note  lengthened 
axis  and  decreased  diameter. 

are  somewhat  earlier-maturing  than  those  of  the  Rose,  and  are 
much  less  profuse  bloomers.  This  is  made  all  the  more  apparent 
by  the  failure  of  a  large  number  of  the  flower  buds  to  fully  expand. 
In  the  potato-growing  regions  of  the  Middle  West,  it  is  still  one  of 


454 


DESCRIPTION  OF  COMMERCIAL  VARIETIES 


GROUP  5.  EARLY  OHIO 


455 


the  leading  commercial  varieties.  This  is  particularly  true  in  the 
Eed  Eiver  Valley  of  Minnesota  and  North  Dakota,  and  in  the  Kaw 
Valley  in  Kansas;  it  applies  equally  as  well  to  other  less  well- 
known  localities. 

Description. — Vines  quite  similar  to  those  of  the  Early  Rose, 
though  as  a  rule  they  are  somewhat  stockier,  do  not  branch  as 


FiQ.  251. — ^A  large  but  well-shaped  and  true-to-type,  Early  Ohio  from  Montana.  Natural  size. 


freely,  and  mature  a  week  to  ten  days  earlier.  Flowers  are  white, 
but  not  quite  so  large  as  in  the  preceding  group;  the  anthers  are 
also  considerably  lighter  in  color,  being  a  lemon-yellow  instead  of 


456  DESCRIPTION  OF  COMMERCIAL  VARIETIES 

a  bright  orange-yellow.  Tubers  are  ovoid  to  round-oblong  or 
cjdindrical,  with  rounded  seed  and  stem-ends  in  ^vell-grown  speci- 
mens (Figs.  247  to  251,  PL  II-E).  Eyes  numerous,  rather  shal- 
low but  strong,  sometimes  protuberant.  Skin  flesh  or  light  pink, 
except  in  the  case  of  the  White  Ohio,  which  has  a  creamy-white 
skin  with  pink  eyes ;  the  seed  end  is  usually  a  deeper  shade  of  pink ; 
surface  of  the  skin  more  or  less  numerously  dotted  with  small. 


P^iG.  252. — A  good  specimen  of  Beauty  of  Hebron. 

raised,  corky  dots  (lenticels)  ;  more  conspicuous  when  grown  in 
some  soils  than  in  others.  Sprouts  short,  much  enlarged  at  the  base, 
color  varying  from  carmine-violet  to  violet-lilac  or  magenta-lilac. 

The  followinj?  varieties  have  been   placed   in  the   Early  Ohio  group: 

Early  Acme.  Late  Ohio. 

Early  Market.  Majestic   (New  Majestic) . 

Early  Ohio.  Prize  Early  Dakota. 

Early  Six  Weeks.  Ratekin's  Red  River  Special. 

White  Ohio. 

Of  the  above  list  the  Early  Market,  Majestic,  Prize  Early  Dakota, 
and  Ratekin's  Red  River  Special  are  simply  Early  Ohio  re-named. 

Group  6.  Hebron. — Tlie  varieties  in  the  IIe1)ron  group  are 
chiefly  distinguished  from  those  of  the  Rose  group  by  the  color 
of  their  tubers.  Most  members  of  the  group  are  early  or  mid- 
season  varieties,  the  only  exception  noted  being  the  Late  Beauty 
of  Hebron.  Thirty-five  years  or  more  ago  tlie  group  had  some 
commercial  importance,  as  botli  the  Early  and  the  Late  Beauty 
of  Hebron  were  rather  extensively  grown.  Their  decadence  has 
been  largely  due  to  the  fact  tliat  ihey  arc  very  susceptible  to  the 


GROUP  G.  HEBRON 


457 


late  blight,  and  they  have  more  or  less  degenerated  or  "run-out." 
Another  and  perhaps  more  important  reason  is  that  they  have  been 
superseded  by  better  varieties.  At  the  present  time  they  are  not 
grown  commercially  in  any  section,  with  the  possible  exception 
of  certain  localities  where  they  are  grown,  to  a  limited  extent,  for 
the  general  seed  trade. 

Description. — Varieties  of  this  group  may,  with  one  exception, 
be  classed  as  second  early  or  mid-season.     The  Late  Beauty  of 


fM 


Fig.  253. — Reproducea  from  original  cut  of  Burbank's  Seedling.    Note  prominent  eyes. 
Group  7,  section  1. 

Hebron  matures  about  the  same  time  as  the  Green  Mountain. 
Vines  very  similar  to  the  Early  Eose.  Flowers  white.  Tubers 
elongated  and  distinctly  flattened,  sometimes  spindle-shaped;  ends 
more  or  less  blunt  (Fig.  252,  PI.  II-F).  Eyes  numerous,  medium 
deep.  Skin  cream3'-white,  more  or  less  clouded  with  flesh  color  or 
light  pink.  Sprouts  very  similar  to  those  in  section  1  of  the 
Early  Eose  group,  but  Mdth  rather  less  color. 

The  varieties  classed  in  this  group  are  as  follows: 

Beauty  of  Hebron    (Early  B.  of  H.). 

Beauty  of  Hebron    (Improved  B.  of  H.). 

Beauty  of  Hebron    (Late  B.  of  H.). 

Columbus. 

Country  Gentleman. 

Crown  Jewel. 

Early  Bovee. 

Gem  of  Aroostook. 


Harbinger. 
Junior  Pride. 
Milwaukee. 
New  Queen. 
Quick  Crop. 
Star-of-the-East. 
Vigorosa. 
White  Elephant. 
White  Hebron. 


458 


DESCRIPTION  OF  COMMERCIAL  VARIETIES 


% 


Group  7.  Burbank.— In  the  early  period  of  its  introduction  the 
Burbank  potato  or  Burbank's  Seedling,  as  it  was  then  knovai,  was 
rather  extensively  grown  in  the  northeastern  part  of  the  United 

States ;  but  for  the  past  quarter 
of  a  century,  its  popularity  as  a 
■'v'-^  commercial  variety  has  waned 

to  such  an  extent  that  it  is  now 
rarely  grown  except  for  seed 
purposes.  In  the  West,  on  the 
other  hand,  it  is  still  quite 
popular  in  many  sections.  The 
russet  type  of  the  Burbank  is 
a  more  recent  acquisition,  and 
is  generally  considered  supe- 
rior to  the  original  Burbank  in 
table  quality.  The  smooth  skin 
or  true  Burbank  type  is  grown 
rather  extensively  in  the 
Stockton  district  in  California, 
and  in  the  western  part  of 
Oregon ;  Avhile  the  russet  types 
are  produced  in  the  Yakima 
Valley  in  Washington,  and 
rather  generally  in  Idaho  and 
in  certain  parts  of  Nevada, 
Utah,  Colorado  and  western 
Nebraska.  The  russet  mem- 
bers of  this  group  are  assigned 
to  section  2. 

Description. — Vines  luishy 
and  inedium  large.  Stems  light 
to  medium  green,  branched 
and  spreading.  Leaves  abun- 
dant and  medium  in  size, 
usually  the  major  leaflets  are 
rather  long  and  narrow,  tapering  to  a  point  which  is  generally 
curved,  medium  green  in  color.  Flowers  not  very  abundant,  many 
falling  off  before  opening;  pedicel  of  flower  cyme  generally  rather 
long  and  erect,  and  usually  standing  M'ell  above  the  foliage ;  calyx 
lobes  rather  long,  usually  extending  well  beyond  the  corolla  before 
flower  opens.    There  are  no  distinguishable  differences  in  the  vine 


Fig.  254. — Reproduced  from  original  cut 
of  the  White  Star  variety.  This  variety  was 
considered  as  a  straight  Burbank  by  several  of 
the  past  generation  of  potato  breeders. 


GROUP  7.  burbank: 


459 


growth  or  floral  characters  of  the  smooth  aiul  russet-skinned  types 
of  the  Burbank. 

Section  1. — Tuliers  long,  cylindrical  to  distinctly  flattened  in 


Fig.  255. — Three  fairly  good  specimens  of  eastern  grown  Burbank  tubers. 


Fig.  256. — Three  good  typical  Wisconsin-grown,  Russet  Burbank  tubers.    Note  moder- 
ate netting  of  skin. 

shape,    inclined   to   be    somewhat    spindle-shaped;    skin    white   to 
creamy- white,  smooth  or  slightly  netted  (Figs.  253-255,  PI.  III-G). 


460 


DESCRIPTION  OF  COMMERCIAL  VARIETIES 


Sprouts,  base  creamy-white,  or  faintly  tinged  with  magenta;  leaf 
scales  and  tips  usually  lightly  tinged  with  magenta. 

Section  2. — Tubers  have  russet  skin,  heavily  netted  or  reticu- 
lated (Figs.  25G  and  257,  PI.  III-G').  In  all  other  respects  than 
color  and  netting  of  the  skin,  the  tuber  characters  of  the  Russet 
Burbank  are  similar  to  those  of  Section  1. 


Fifi.  257. — Tuber  "A"  rcprosonts 
sents  a  broader,  flatter  shape  which  is 
typical  in  netting  of  most  western-growi 
other  western  states. 

The  varieties  given  below 
Section  1.  Burbank  or  Biirl)ank's 
Late  Puritan. 
Money  Maker. 
]'ri(lc  of  ]\Iultnomah. 
White  Beauty. 
White  Chief. 


m  ideal-shaped  Russet  Burbank.  Tuber  "B"  repre- 
not  considered  desirable  for  seed  stock.  Tubers  are 
1  stock  such  as  may  be  tound  in  Colorado,  Idaho  and 

are  considered  members  of  this  group : 
Seedling.  Section  2.  California  Russet. 

Cambridge  Russet. 

Golden  Russet  (Old's). 

Netted  Gem. 

New   Wonderful. 

Russet  Burhank. 

Rusty  Coat. 

Seabproof   (Salzer's). 


GROUP  8.  GREEN  iMOUNTAIN  461 

Group  8.  Green  Mountain. — The  members  of  the  Green  Moun- 
tain group  may  be  said  to  divide  lionors  with  those  of  the  Kural 
in  their  commercial  importance  as  a  late  or  main-crop  variety. 
They  seem  to  be  peculiarly  well  adapted  to  northern  latitudes, 


FiG.zoS. — -Three  good  specimens  of  Wisconsin-grown  Green  Mountain  tubers. 


Fig.  259. — A  good  tj-pe  specimen  of  Green  Mountain. 

where  the  rainfall  is  al)undant  and  the  temperature  is  not  exces- 
sively high.  As  a  rule  they  do  not  succeed  as  well  in  localities 
where  they  are  subjected  to  unfavorable  conditions  of  growth  during 
the  time  they  are  forming  tubers,  as  do  the  members  of  the  Rural 
group.     Recent  observations  indicate  that  most,  if  not  all,  of  the 


462 


DESCRIPTION  OF  COMMERCIAL  VARIETIES 


members  of  this  group  are  peculiarly  susceptible  to  mosaic  infection 
of  the  foliage  with  a  consequent  material  reduction  in  the  yield 
of  the  tubers.  They  are  also  among  the  most  susceptible  to  late 
blight  infection  of  both  vine  and  tuber. 

The  varieties  in  this  group  are  divided  into  two  sections,  accord- 
ing to  whether  they  have  white  or  slightly-colored  sprouts. 

Descripiion. — Vines  large,  strong  and  well-branched.  Stems 
light  green  in  color,  usually  distinctly  winged.    Leaves  large,  leaf- 


FiG.  200. — Cross  section  of  a  Green  Mountain  tuber.     Natural  size. 

lets  broad,  smooth  and  more  or  less  flaccid,  medium  green.  Flowers 
abundant,  white,  fair  size,  rarely  producing  seed  balls  naturally, 
except  under  very  favorable  climatic  conditions.  Tubers  moder- 
ately to  distinctly  oblong,  usually  broad-flattened  with  more  or 
less  blunt  ends  (Figs.  258-260,  PL  III-H) ;  eyes  medium  in  num- 
ber, rather  shallow,  -nath  strong  bud-eye  cluster.  Skin  a  dull 
creamy-white  or  light  russet  color  when  well  netted.  Sprouts  in 
section  1  rather  short  and  stubby,  base,  leaf  scales  and  tips  creamy- 
white,  w^hile  in  section  2,  with  the  exception  of  Twentieth  Century, 
they  are  mostly  without  color  at  the  base;  the  leaf  scales  and  tips 
are  usually  faintly  or  distinctly  tinged  ^nth  lilac  or  magenta. 


GROUP  9.  THE  RURAL 


463 


The   following  varieties   have   been   classed   in   the   white   sprout  division! 
Section  1. 


Bethel  Beauty. 

Bishop's  Pride. 

Blightless  Wonder. 

Bugless   (Gurney's  Bugless). 

Clyde. 

Delaware. 

Farmer. 

Freeman. 

Gold  Coin. 

Green  Mountain. 

Green  Mountain  Jr. 

Green  Mountain   (Lowell's). 

Basting's   (2). 

Keystone. 

Section  2. 
American  Giant. 
Carman   No.   L 
Empire  State. 


Late  Blightless. 

Long  Island  Wonder. 

McGregor. 

McKinley  Mill's  Pride. 

New  Oregon. 

Norcross. 

Pride. 

Silver  King  (2). 

Snow. 

Uncle  Sam. 

Washington,  t 

White  Harvest    (Gurney's). 

White  Mountain. 


Longfellow. 
Rustproof. 
State  of  Maine. 


Group  9. — The  Rural  group  includes  a  large  number  of  strong- 
growing,  late-maturing  varieties.     Collectively  they  are  now  com- 


FiG.  261. — Upper  and  lower  view  of  a  Rural  New  Yorker  No.  2  tuber. 

monly  referred  to  by  ISTew  York  State  growers  as  "blue-sprout" 
potatoes,  in  contradistinction  from  the  "white-sprout"  varieties 
belonging  to  the  Green  Mountain  group.  The  members  of  the 
Eural  group  seem  to  be  admirably  adapted  to  southern  and  western 
t  Classified  by  A.  L.  Dacy,  Exp.  Sta.,  Morgantown,  W.  Va. 


.464 


DIOSCRIPTION  OF  COMMERCIAL  VARIETIES 


New  York,  and  to  certain  sections  of  Michigan,  Wisconsin,  Iowa, 
and  Minnesota.  The  tubers  keep  Avell  in  storage  and  are  slow  to 
germinate  in  the  Spring.  The  vines  develop  slowly  at  first,  but, 
as  tlie  season  advances,  they  branch  rather  freely  and  develop  fairly 


Fig.  2()2. — Four  tubers  of  Rural   New  Yorker   No.  2,  showiuc  variation   in   position 
and  depth  of  the  terminal  eyes  or,  as  they  are  more  generally  known,  the  bud-eye  cluster. 

large  plants.  Tuber  formation  seems  also  to  be  delayed,  but  when 
the  right  growing  conditions  prevail,  in  the  latter  part  of  the 
season,  they  grow  very  rapidly  and,  if  the  season  of  favorable  growtli 
is  prolonged,  the  larger  tubers  are  quite  apt  to  be  hollow-hearted. 
As  a  group,  the  tubers  are  of  desirable  shape,  attractive  color,  and 


GROUP  9.  THE  RURAL 


465 


fair  taljle  qualit}',  uiid  the  vines  are  fairly  resistant  to  drought  and 
to  diseases  other  than  late  hlight. 

As  in  the  case  of  the  Burbaid<;  group,  two  sections  have  been 
created  in  order  to  include  the  Eusset  Eurals,  which,  save  for  the 
color  of  the  skin  and  a  heavier  netting,  are  practically  identical 
in  every  other  respect  with  those  of  the  white-skinned  varieties 
included  in  section  1,  the  one  description  answering  for  both. 

Description. — Vines  medium  large.  Primary  stem  upright, 
usually  long-jointed,   and   rather   sparsely   covered   with   foliage; 


Fig.  263. — Cross  section  of  a  Rural  New  Yorker  No.  2  tuber.     Natural  size. 

lateral  branches  more  or  less  decumbent,  giving  the  plant  a  straggly 
appearance.  Stems  more  or  less  distinctly  streaked  with  dark 
purple.  Leaves  medium-sized  to  rather  small,  dark  green,  more 
or  less  rugose  or  crumpled  and  leathery  or  firm  to  the  touch. 
Flowers  medium  to  fairly  abundant  in  some  varieties  and  of  fair 
size;  the  central  portion  of  the  corolla  deep  violet-purple  with  the 
color  growing  lighter  toward  the  outer  portion;  five  points  of  the 
corolla  white  or  nearly  so.  Tubers  broadly  round-flattened  to 
short-oblong,  or  distinctly  oblong-flattened  (Figs.  261-2G3,  PI. 
IIT-I).     Eyes  few,  very  shallow,  bud-eye  cluster  strong  and  usually 


466  DESCRIPTION  OF  COMMERCIAL  VARIETIES 

depressed.  Skin  creamy-white  and  occasionally  netted  in  the 
varieties  of  section  1,  while  in  those  belonging  to  section  3,  the 
skin  is  a  deep  russet  color  and  much  netted.  Sprouts  short,  base 
enlarged,  dull  white;  leaf  scales  and  tips  medium  to  deep  violet- 
purple  or  pansy-violet. 

Section  1. 

The  varieties  classified  under  section  1  seem  to  be,  in  most  cases 
at  least,  the  result  of  a  re-naming  of  old  varieties. 

Arcadia.  Ohio  Wonder. 

Banner    (Livingston's  Banner).  Pan  American. 

Carman  No.  3.  Peerless   (Bresee's  No.  6)  or  Boston. § 

Dooley's.  Potentate. 

Doolin,  John.  Prince  Henry. 

Great  Divide.  Prosperity. 

Hart's  No.  1.  Rhind's  Hybrid. 

Improved  No.  5.  Rural  New  Yorker  No.  2. 

Isle  of  Jersey.  Sensation. 

Jackson  White.  Sir  Walter  Raleigh. 

Late  Beauty   (Heath's  L.  B.).  Snowflake  Jr.  | 

Late   Surprise    (Heath's   med.-late).      Todd's  Wonder. 

Late  Victor.  Uncle  Sam.  || 

Lily  White.  White  Giant. 

Manila.  White  Swan. 

Market  Prize.  %  White  Globe. 

Million  Dollar. 

Nebraska. 

Non-Blight. 

Noxall. 

Section  2. 
Golden  Harvest.  Late  Petoskey   (Rural  Russet). 

Golden  Rule.  Russet  Rural    (Dibble's  Russet). 

Golden  Rural. 

Group  10. — The  Pearl  group  is  one  of  the  smallest  and  at  the 
same  time  one  of  the  least  known,  so  far  as  its  origin  is  concerned. 
It  is  chiefly  grown  in  Wisconsin,  Nebraska,  Colorado,  and  Idaho. 
There  are  three  distinct  types  in  the  group,  the  first  of  which  is 

§  Not  the  true  Bresee's  Peerless,  though  listed  as  such. 

X  A.  L.  Dacy's  Classification. 

II  At  the  present  time  there  seems  to  be  two  distinct  varieties  bearing 
the  name  of  "Uncle  Sam."  One  belongs  to  the  Green  Mountain  and  the 
other  to  the  Rural  Group.  The  original  "  LTncle  Sam"  is  a  member  of 
the  Green  Mountain  group 


GROUP  10.  THE  PEARL 


467 


represented  by  the  Pearl,  the  second  by  People's  and  the  third  by 
Blue  Victor,  from  which  the  Pearl  probably  owes  its  origin  as  a 
bud  variation  or  sport.  The  members  of  this  group,  like  those  of 
the  Triumph  and  Green.  Mountain,  are  very  susceptible  to  mosaic; 
and  it  is  becoming  increasingly  difficult  to  produce  or  to  purchase 
disease-free  seed. 

Description. — Maturing  about  with  Green  Mountain.  Vines 
medium  to  large,  strong,  healthy  and  as  a  rule  Avell-branched ; 
stems  dark  green  (in  section  3  streaked  with  purple),  more  or  less 
upright  in  early  stages  of  gro^^h,  but  gradually  assuming  a  some- 
what decumbent  position  as 
the  plant  approaches  matu- 
rity. According  to  Fitch- 
the  main  stem  of  the  Pearl 
should  assume  a  more  or  less 
horizontal  position,  and  the 
lateral  branches  an  upright 
position.  Leaves  medium  to 
large  in  size,  rather  fiat, 
somewhat  rugose,  and  ap- 
proaching dark  green  when 
well  grown.  Flowers  not 
abundant,  and  many  of  the 
buds  that  do  form  drop  off 
either  in  the  bud  or  just  prior 
to  opening;  corolla  is  white 
with  pale  lemon-yellow 
stamens.  When  plants  are 
normal,  they  do  not,  as  a 
rule,  produce  many  seed  balls, 
to  large  in  size  and  in  favorable  growing  seasons  often  get  large  and 
of  uneven  shape.  N'ormal  tubers  are  round-flattened  to  heart- 
shaped  flattened,  usually  heavily  shouldered  due  to  deep  recession 
of  stem  (Figs.  264  and  265,  and  PI.  I-C).  Eyes  rather  shallow, 
sometimes  protuberant,  or  in  off -type  specimens  inclined  to  be  deep 
with  heavy  eyebrows.  The  bud-eye  cluster  in  a  normal  specimen  is 
shallow,  while  in  an  abnormal  one  it  is  usually  distinctly  depressed. 
When  freshly  dug,  the  Pearl  has  a  distinct  pinkish  or  light  purple 
tinge  around  the  eyes,  particularly  at  the  seed  end ;  exposure  to  the 
light  or  prolonged  storage  seems  to  reduce  the  color  to  such  an 


Fig.  264. — Four  views  of  Pearl  tubers. 


Tubers  in  section  1  are  medium 


468 


DESCRIPTION  OF  COMMERCIAL  VARIETIES 


extent  that  it  is  scarcely,  if  at  all,  visible.  Skin  a  dull  white, 
generally  more  or  less  netted.  Sprouts  have  base,  leaf  scales  and 
tips  slightly  or  distinctly  suffused  Anth  light  lilac. 

Secfion  2. — The  tubers  of  the   People's  potato,  which  is  the 
sole  member  of  tliis  section,  are  so  nearly  identical  in  every  respect, 

except  in  color  of  skin,  as  to 
make  it  unnecessary  to  do 
more  than  describe  the  color 
which,  when  well  grown  in 
the  lava  ash  soils  of  southern 
Idaho,  is  a  rich  russet-brown. 
The  russet  color  is  not  due  as 
in  the  case  of  the  Eusset 
Burbank,  to  a  heavy,  corky- 
Ijrown  growth,  but  rather  to 
a  coloration  of  the  skin  it- 
self. It  is  the  same  kind  of 
pigmentation  as  is  found 
in  some  of  the  Russet 
Rural  varieties,  such  as  the 
Golden  Rural. 

Section  5.— The  Blue 
Victor  is  the  sole  member  of 
this    section    and    its    tubers 


Fig.  205. — A  very  good  type  of  the  Pearl 


differ  from  the  Pearl  in  that  they  are  a  deep  blue  color,  frequently 
with  creamy-white  splashes  around  the  eyes.  The  sprouts,  base, 
leaf  scales  and  tips  are  a  vinous-mauve. 

The  varieties  belonging  to  the  Pearl  group  are  as  follows: 
Section  1.  Section  2.  Section  3. 

Dearborn  People's  Blue  Victor 

Pearl 
Rehoboth 

The  Dearborn  and  IJehoboth  arc  considered  identical  Avith 
the  Pearl. 

Group  II. — The  Peachblow  group  is  an  interesting  one 
because  it  is  the  oldest  of  the  twelve  groups  given.  The  "old- 
timer"  or  tlie  potato  grower  of  50  years  ago,  usually  harks  back  to 
the  large  yields  and  excellent  table  qualities  of  the  Old  Jersey 
Peachblow,  and  constantly  regrets  that  it  has  been  allowed  to  dis- 
appear. During  the  past  half  century  or  more  a  considerable 
number  of  Peachblow  varieties  have  come  and  gone  until,  at  the 


GROUP  11.  THE  PEACHBLOW  469 

present  time,  there  are  practically  but  two  members  of  this  group 
that  are  now  grown  comjnercially  in  the  United  States.  These 
varieties  are  the  Improved  Peachblow  and  the  McCormick.  The 
former  is  grown  in  a  limited  way  in  some  sections  in  Colorado  and 
the  latter  as  a  late  crop  throughout  a  large  portion  of  the  South, 
beginning  with  Maryland  and  extending  to  Georgia.  This  group 
is  characterized  by  the 
extreme  health  and  vigor 
of  its  vines.  It  includes 
some  early  varieties,  but 
for  the  most  part  they 
are  late  to  very  late  in 
maturing. 

The    McCormick   is        i^,  ^^, 

the    most    dependable        "*  ^^^ 

variety  that  we  have  to 
grow  as  a  late  crop  in  the 
South,  as  it  is  the  only 
variety  that  will  success- 
fully  withstand  t  h  e 
extreme  heat,  and  occa- 
sionally extreme  drought 
as  well,  and  at  the  same 
time  make  a  fair  crop  if 
rain  and  cool  weather 
come  early  enough  in  the  *'i£*''" 

Autumn   to   give    the 

Tt(iOf^(i^aT^^    timp    for  ^i"-  206.— A   fairly  representative  McCormick 

necessary    time    l  O  r       ty^er.     Note   number  and  depth  of  eyes. 

tuber  development. 

Description. — Vines  strong,  erect,  healthy,  vigorous  and  deep- 
rooted.  Stems  large,  strong,  woody,  and  medium  green  in  color. 
Leaves  medium  in  size  and  abundance,  rather  thick,  rugose,  or 
crumpled,  medium  to  large  in  size  and  rather  dark  green.  Flowers 
usually  abundant,  purple,  and,  in  the  case  of  the  McCormick, 
inclined  to  set  fruit  rather  freely  when  conditions  are  favorable. 

Section  1. — The  tubers  are  roundish  or  ovoid,  to  round-oblong, 
somewhat  flattened.  Eyes  numerous  and  usually  quite  deep  (Fig. 
266,  PI.  IV-J),  invariably  suffused  with  carmine  or  crimson,  the 
intensity  of  which  is  more  or  less  variable.  Skin  creamy-white  to 
white  splashed  with  crimson  or  magenta  or  flesh  colored.  Sprouts 
have  base,  leaf  scales  and  tips  of  reddish-violet. 

Section  2. — The  tubers  are  round-Jhitteiied  to  lieart-shape  Hat- 


470 


DESCRIPTION  OF  COMMERCIAL  VARIETIES 


teiied.     Eyes  few,  mostly  at  seed  end,  very  shallow  except  bud-eye 
cluster,  which  is  generally  more  or  less  depressed    (PI.   IV-K). 
Skin  a  deep  reddish-pink  or  magenta,  carmine  colored  around  the 
eyes.     Sprouts  similar  to  those  in  section  1. 
Section  1. 


Dvkeman. 

Early   Peachblow    (Hall's). 
Extra  Early  Peachblow. 
Jersey  Peachblow. 
McCorniick   (pink). 
McCormick  ( white ) . 


Section  2. 
Improved  or  Perfect  Peachblow   ( Rand's ) , 

Synonym.   Red  McClure. 
New  Improved  Peachblow    (Nichols'). 
New   White  Peachblow    (Thorburn's). 
White  Peachblow. 
Nott's  Peachblow. 


Group  12.  The  Up-to-Date  group  of  potatoes  is  of  Euro- 
pean origin.     The  leading  member  of  the  group,  Up-to-Date,  was 


Fio.  267. — A  good  type  tuber  of  the  Up-to-Date  variety.   Note  fewness  of  eyes  and  gen- 
eral smoothness  of  tuber. 

originated  by  Archibald  Findlay  of  Scotland  in  the  late  eighties, 
and  ranks  among  the  leading  late  or  main-crop  potatoes  of  Great 
Britain.  The  Factor,  introduced  by  Sutton  and  Sons  of  Eeading, 
England,  is  so  nearly  identical  M'ith  Up-to-Date  as  to  be  practically 
indistinguishable  from  it.  Both  of  these  varieties  were  introduced 
by  the  United  States  Department  of  Agriculture  in  the  spring  of 
1905,  and  have  been  continuously  grown  in  the  Department's 
variety  collection  since  that  date.    Within  the  past  few  years  some 


GROUP  12.  THE  UP-TO-DATE  471 

varieties  have  been  offered  by  seedsmen  under  American  names  tliat 
are  very  similar  to  Up-to-Date.  The  members  of  this  group  do 
not  appear  to  have  a  very  wide  range  of  adaptation  in  this  country, 
but  where  they  have  been  tested  under  good  environmental  con- 
ditions, they  have  made  a  very  satisfactory  crop.  They  are  best 
adapted  to  rather  heavy  soils,  and  to  a  rather  cool  climate,  such 
as  may  be  found  in  the  Northwest,  where  it  proved  extremely  satis- 
factory at  the  Western  Washington  Station,  Puyallup,  Washington. 
Descriplion. — Vines  medium  to  large.  Stems  quite  large,  and 
woody,  decidedly  angular,  dark  green.  Leaves  medium  size,  ratlier 
thick,  and  having  a  peculiar  twisted  appearance;  dark  green. 
Flowers  rose-purple,  moderate  to  rather  profuse  bloomers;  pistil 
thick  and  usually  twisted  or  curved ;  stamens  seldom  if  ever  produc- 
ducing  viable  pollen.  Tubers  oblong-flattened  to  somewhat  obovate- 
flattened,  usually  of  a  good  size.  Eyes  few,  very  shallow,  mostly 
at  seed  end  (Fig.  267,  PI.  IV-L).  Skin  creamy-white,  moderately 
netted  or  nearly  smooth. 

The  following  varieties  have  been  classed  in  the  Up-to-Date  group 
by  Henshaw.^ 

Col.   Staney.  Gen.  Roberts. 

Conquering  Hero.  Heather  Blossom. 

Cottar.  Highlander. 

Dalhousie  Seedling.  King  Loth. 

Dalmeny  Argon.  Motor. 

Dalmeny  Beauty.  Nobleman. 

Dalmeny  Helium.  Scottish  Monarch. 

Dalmeny  Hero.  Scottish  Triumph. 

Dalmeny  Regent.  Sensation. 

Duchess  of  Buccleugh.  Sir  Mark  Stewart. 

Duchess  of  Cornwall.  Superlative. 

Dumfries  Model.  Table  Talk. 

Enquirer.  Talisman. 

Factor.  Up-to-Date. 

Warrior. 

Only  two  of  the  foregoing  varieties  liave  come  under  the  writer's 
observation,  viz.,  Factor  and  Up-to-Date.  In  addition  to  these, 
several  varieties  now  listed  by  American  seedsmen  have  been  studied 
and  assigned  to  this  group.     These  are 

Bull  Moose.  Producer. 

Cumming's   Pride.  Pres.    Roosevelt. 

Gold  Standard.  Solanum  Sp.    (from  South  America). 

Moreton.  Verbots   (from  South  America). 

Bull  Moose  is  quite  popular  in  southern  Indiana  and  in  the 
Louisville  district  in  Kentucky. 


472  DESCRIPTION  OF  COMMERCIAL  VARIETIES 

QUESTIONS  ON  THE  TEXT 

1.  What  scheme  of  classification  was  first  advocated?     By  whom? 

2.  Give  the  next  suggested  system  of  classification.     By  whom? 

3.  How   did    the   third    system   difl"er    from   the    second    one?      By   whom 

submitted  ? 

4.  Who  was  the  first  to  devise  a  classification  system  in  the  United  States? 

5.  On  what  was  his  grouping  based?     How  many  groups?     Name  them. 

How  subdivided? 

6.  What  changes  did  Kohler  make  in  his  later  classification? 

7.  What  variety  classification  did  Ballou  offer? 

8.  What  variety  classification  did  Milward  present? 

9.  How  does  this  classification  compare  with  Kohler 's? 

10.  How  many  groups  did  Fitch  make  in   1914?     Name  them. 

11.  In  what  respects  is  this  an  improvement? 

12.  Give  iSnell's  classification. 

13.  Give  author's   (Stuart's)   classification. 

14.  How  does   this  differ   from  the  preceding   ones?      How  many   groups? 

15.  Wliat   other   character   has   been   suggested   by   Kranz   for    the    identi- 

fication of  the  groups? 

16.  Of  what  value  is  the  group  system  in  studying  varietal  relationships? 

17.  Give   the   classification   key    offered    in    this    chapter    for    each    group. 

18.  What  is   said   regarding  group    12? 

19.  Give  the  chief  characteristics  of   the  Irish   Cobbler  group. 

20.  To   what    sections    and    climatic    conditions    is    the    Irish    Coljbler    best 

suited?     Discuss  it  as  an  early  truck  crop. 

21.  What  varieties  or  so-called  varieties  belong  to  this  group? 

22.  Describe  the  Triumph  group,  and  compare  the  members  with  those  of 

the  Irish  Cobbler  group. 

23.  Where  is  the  Triumph  most  extensively  grown? 

24.  What  varieties  or  so-called  varieties  belong  to  this  group? 

25.  Of  what  commercial  importance  is  the  Early  Michigan  group?     Where 

chiefly  grown? 

26.  Describe  the  Early  Michigan  group?     Name  the  varieties. 

27.  How  do  the  Aarieties  belonging  to  the  Early  Rose  compare   in   point 

of  numbers  to  those  of  the  other  groups? 
2S.  Of  what  importance  is  this  group  commercially? 
29.  Describe  the  sections  of  the  Early  Rose  group. 
;!0.  What  varieties  belong  to  each? 
31.  Is  there  any  general  similarity  between  the  Early  Rose  group  and  the 

Early  Ohio  group?     Give  differences. 
?>2.  Where    is    the   Early   Ohio    most   extensively    grown?      Give   varieties. 

33.  Describe   the   Early   Ohio,   giving   characteristics    of   plant    and    tuber. 

34.  In   what    respect   do   the   varieties    of    the    Hebron   group    differ    from 

those  of  the  Early  Rose?     Describe  the  former. 

35.  To  what  is  the  decadence  of  this  grouj)  due?     Give  varieties. 

36.  Where   is  the  Burbanlc  group  of  potatoes  commercially  grown? 

37.  Name  the  sections  of  the  group.     Name  varieties  of  each. 
I'S.  Describe  and  compare  the  two  sections. 

39.  What   sections   and   conditions  best   suit   the   Green   Mountain   group? 

40.  To  what   diseases   are  its   members   peculiarly   susceptible?     Describe 

the  group. 


REFERENCES  CITED  473 

41.  Into  how  many  sections  is  the  group  divided?     Give  basis  of  division. 

42.  What  varieties  belong  to  each  section? 

43.  Describe  the  plant  and  tuber  characters  of  the  Rural  group. 

44.  To  what  section  of  the  country  is  it  adapted? 

45.  Give   the   names    of   as   many   varieties   as    possible    under    section    1. 

46.  Name  the  varieties  belonging  to  section  2. 

47.  For  what  is  the  Pearl  group  chiefly  distinguished?    Describe  the  group. 

48.  How   many   distinct   tuber   types   are   there   in   the   group? 

49.  Distinguish  between   the   sections. 

50.  Describe  the  People's  potato. 

51.  Describe  the  Blue   Victor. 

52.  Name   the  varieties  belonging  to   the  three  sections. 

53.  How  many  real  commercial  varieties  belong  to  the   Peachlilow  group 

at  tlie  present  time?     Name  them  by  sections. 

54.  What  member  of  this  group   is  especially  adapted   to  the  production 

of  a  late  crop  of  potatoes  in  the  South?     How  so  adapted? 

55.  Describe   the   Peachblow    plant    and    the   tubers    in    sections    1    and   2. 
5ti.  What   varieties   belong    to    sections    1    and    2? 

57.  What  is  the  history  of  the  Up-to-Date  group?     Give   adaptation. 

58.  Describe  the  vine  and  tuber  characteristics. 

59.  Name  the  varieties   included   in   this   group   which   are   or   have   been 

offered  to  the  trade  by  American   seedsmen. 

QUESTIONS  AND  EXERCISES  SUGGESTED  BY   THE  TEXT 

1.  Make  a  rather  complete  list  of  the  varieties  of  potatoes  grown  locally. 

2.  From  dealers  and  growers  obtain  standard  samples  of  each  of  these. 

Learn   to   know   standard   samples   of   leading   varieties. 

3.  Determine  from  name,  as  well  as  from  characteristics,  to  what  group 

each   belongs. 

4.  With  these  on  exhibit  plates,  -write  labels  on  cards  for  each  and  include 

group  names  and  synonyms.      Learn  to  know  the  groups  better 
by   this   exercise. 

5.  Prepare   an    appropriate   premium    list    to   cover    all    the   groups   and 

varieties  likely  to  be  grown  in  your  county  or  state. 

6.  Make  a  large  drawing  showing  plans   for   a  large   booth   on   potatoes 

at  a  fair. 

7.  Make  up  a  list  of  several  questions  for  debate  on  potato  topics. 

8.  On  one  of  these  questions,  concerning  varieties,  outline  the  arguments 

on  both  sides  of  the  debate. 

References   Cited 

1.  Ballou,    F.    H.      1910.      A    practical    classification    or    grouping    of 

varieties  of  potatoes.     Ohio  8ta.  Bui.  218:    593-595,  June,    1910. 

2.  Fitch,    C.    L.      1910.      Productiveness    and    degeneracy    of    the    Irish 

potato.     Col.  Hta.  Bid.   176:    16,  1910. 

2  (a). 1914.    Identification  of  potato  varieties.    loica  Agr.  Exten.  Dept. 

Bui.   20:    16-32,  April,    1914. 

3.  Hexsiiaw,  H.     1911.     Experiments  in  potato  growing.     Jour.  Bd.  Agr. 

(London)    17:   892-904,   1911    (see  p.   901). 

4.  KoHLER,  A.  H.     1909.     Potato  experiments  and  studies  at  University 

Farm.    Minn.  8ta.  Bui.  114:  311-319,  1909. 


474  DESCRIPTION  OF  COMMERCIAL  VARIETIES 

4    (a). 1910.     Potato  experiments  and  studies  at  University  Farm  in 

1909.     Minn.  Uta.  Bui.   118:  65-141,  1910. 
5.  Kbanz,   F.  a.      1918.     The  position  of  the  flower  stalk   as  a  help   in 

potato  identification.     The  Pot.  Mag.   1:   13,  Nov.,  1918. 
G.  Lenne.      1855.     Abs.   U.    S.    Patent   Office   Rpt.    1855:    210-217,    1855. 

Abs.  Jour,  filr  Landwirthsschaft  etc.,  3rd  Jahre,  Erste  Abtheilung: 

250-252,  1855. 

7.  MiLWARD,   J.   G.      1912.      Commercial    varieties   of   potatoes    for   Wis- 

consin.    Wis.  Sta.  Bid.  225:  7,  1912. 

8.  Putsch,  C.  W.   E.  and   F.   J.  Vertuch.     1819.     Versuch  einer  Mon- 

ographie  der  Kartoffeln,  etc.,  Weimar  1819:  1-158,  13  pis.,  8  figs, 
of  foliage  and  blossoms,  33  figs,  of  colored  tubers. 

9.  Snell,  K.      1921.     Kartoffelsorten   Arbeiten   zu   einer   allegemein   und 

speziellen  Sortenkunde.  Arbeiten  des  Forschungsintitutes  filr 
Kartoffelbau,  etc..  Heft  5  p.  1-78,  10  figs.,  2  col.  pis.,  Berlin,  1921. 

10.  Stuart,  W.      1915.     Group  classification  and  varietal  descriptions  of 

some  American  potatoes.  U.  /S'.  Dept.  Agr.  Bui.  176:  1-56, 
March,   1915,    (see  p.   3-13). 

11.  ViLMORiN,  C.   P.  H.  L.      1882,   1886,   1902.     Catalogue  Methodique  et 

Synonymique  des  Principales  Varietes  des  Pommes  de  Terre. 
Paris,  1882.  Ed.  2,  corr.  et  aug.  de  plus  de  200  varieties,  51  p., 
Paris,  1886.  Ed.  3,  refond.  et  aug.  de  plus  de  six  cents  varieties, 
37   p.,  Paris,   1902. 


APPENDIX 


STUDENT'S  PROJECT  IN  GROWING  A  FIELD 
OF  POTATOES  FOR  PROFIT 

In  the  following  outline  it  is  assumed  that  this  project  begins 
with  fall  preparation  of  the  field,  and  continues  through  the  cycle 
until  the  potatoes  are  stored  and  marketed  the  following  fall  and 
winter.  If  desired,  the  project  may  begin  in  the  spring  instead. 
The  operations  would  be  in  the  same  order,  and  this  outline  would 
serve  the  same  purpose. 

The  citations  for  study  in  the  third  column  are  to  chapters  in 
this  volume.  At  the  end  of  each  chapter  other  references  will 
be  found. 

Citations 

to 
Chapters. 


Project  operations. 
Select  field. 


Study  involved. 

Desirable  soil ;  warm  or  cold  soil ; 
physical  texture  of  soil;  mois- 
ture; fertility;  best  crop  to 
precede  potatoes. 

Time  of  plowing:  Advantages  of 
fall  plowing  and  conditions  un- 
der which  it  may  be  inadvisable 
to  do  it. 

Compare  varietal  groups ;  varietal 
suitability  to  soil  and  climate; 
disease  resistance ;  produc- 
tivity;  market  requirements. 

Value  of  good  seed ;  certified  seed ; 
sources  of  good  seed ;  cheapness 
of  good  seed  and  costliness  of 
poor  seed. 

Why  buy  seed  potatoes  ?     Need  of 
early "  purchase    of    seed ;    best 
method  of  storing  seed  during 
late  fall  and  winter  months. 
Selection   and  purchase  of   Kind    and    amount    of    fertilizer 


Plowing. 


Selection    of   suitable   va 
riety. 

Source  of  seed  stock. 


Purchase  of  seed  stock. 


commercial  fertilizers. 


Home  mixing  of  fertilizers. 

Make  winter  study  of  dis- 
eases and  insects. 


to  buy ;  cooperative  buying. 
Desirability  of  early  purchase. 

Advantages  of  home  mixing; 
methods ;    cost. 

Local  enemies  of  the  potato;  na- 
ture and  prevention  of  diseases, 
methods  of  combating  insects; 
sprays  to  use;  spraying  appa- 
ratus; field  treatments  to  pre- 
vent diseases  and   insects. 


Ill,  IV,  V. 


IV. 


VII,  XXI, 
XXII. 


VII. 

VII,  XIII. 

V. 
V. 


XV,  XVI, 
XVII. 
475 


476 


APPENDIX 


Make  plans  for  storage  pits 
and  storage  houses. 


Make  winter  study  of  mar- 
kets. 


Preparation    of    land    and 
application  of   fertilizer. 


Prepare  seed. 


Planting  seed. 


Early  tillage. 


Tillage   after   germination. 

Combating  enemies  and  con- 
trolling diseases. 

Construction      of      storage 
house. 


Field  selection  of  seed  pota- 
toes. 


Harvesting  of  crop. 


Marketing  the  crop. 


Principles  of  storage;  drainage; 
temperature  control;  ventila- 
tion; light  exclusion;  mate- 
rials needed ;  cost  estimates  per 
bushel  capacity. 

Charting  market  prices  in  local 
and  distant  markets;  compare 
prices  for  a  series  of  years 
where  possible;  best  time  to 
market  potatoes;  relation  to 
variety   and   season. 

Plowing  under  green  manure; 
barnyard  manure ;  time  of  oper- 
ation ;  benefits ;  depth  of  plow- 
ing; costs  after  treatment; 
marking  or  laying  otf  rows; 
compare  kinds  of  stable  manure 
for   potatoes;    fresh  or   rotted. 

Treatment  of  seed  potatoes ; 
quantity  of  seed  to  prepare  per 
acre;  greening;  vitality;  cut- 
ting; size  of  seed  piece;  hold- 
ing cut  seed ;  dusting  cut  seed. 

Time;  methods;  types  of  plant- 
ers ;  distances ;  depths ;  ferti- 
lizing at  planting  time. 

Pre-germination  tillage;  benefits; 
implements;  methods;  number 
of   times. 

Purposes;  implements;  frequen- 
cy;  depths. 

Objects  of  spraying;  materials; 
frequency  of  application ;  spray 
outfits ;    results. 

Review  plans  and  lists  of  mate- 
rials made;  dimensions  needed; 
location;  probable  cost  of  ma- 
terial and  labor;  advisability 
of   building,   etc. 

Object  of  field  selection.  How 
and  when  to  select  In  field. 
Improvement  by  selection.  Hill- 
to-row  plan  of  improvement; 
mass  selection;  strain  test; 
storing  seed  potatoes. 

Time;  relation  to  market  de- 
mands; transportation;  prices; 
methods  of  harvesting;  meth- 
ods of  picking;  best  containers; 
handling  when  harvested. 

Conditions  of  market;  size  and 
condition  of  crop  both  as  a 
whole  and  locally;  what  por- 
tion to  market  at  harvest  time; 


XIII,  XIV. 


XII. 


IV,  V 


VII. 


VIII. 


VIII. 


XV.    XVI. 
XVII. 


XIII.  XIV 


XXI. 


XII. 


APPENDIX 


477 


storing  crop,   and  advisa- 
bility of  same. 


Soil  sanitation. 


Cost  accounting. 


Financial  summary. 


grading  and  sorting  to  size; 
containers  for  marketing;  haul- 
ing;   cost  of  marketing. 

Methods  of  handling  for  storage; 
soundness  of  stock;  danger  of 
shrinkage;  other  risks;  proba- 
ble benefits  of  storage.  When 
is    storage    not   profitable? 

Crop  rotation;  crops  to  use  for 
rotation  purposes ;  connection 
between  crop  rotation  and  fun- 
gous and  insect  and  animal 
pests;  length  of  rotation;  use 
of  cover  crops. 

Cost  of  man  and  horse  labor  in- 
volved in  the  production  of 
the  crop ;  cost  of  seed  potatoes ; 
cost  of  fertilizers  (chemical, 
stable,  and  green  manures)  ; 
cost  of  fungicides  and  insecti- 
cides ;  storage ;  marketing ; 
rental  of  land;  interest  on 
money  invested  in  crop;  re- 
ceipts from  crop.  Keep  close 
record  of  every  item  of  ex- 
pense and  income.  Determine 
cost  per  bushel  and  per  cent 
of  profit.  Study  cost  account- 
ing. 

Prepare  financial  analysis  from 
cost  accounting  data.  Write 
in  narrative  form  a  complete 
record  of  procedure  and  results. 


VII. 


XII,  XIII. 


y,  VI. 


XI. 


XI. 


DEMONSTRATIONAL  AND  INSTRUCTIONAL 
FEATURES  IN  POTATO  PROJECTS 


1.  When  fighting  potato  l)eetles,  compare  spraying  methods  with 
dusting. 

2.  Compare  yields  from  different  kinds  and  amounts  of  commercial 
fertilizers,   farm  manure  or  green  manure. 

3.  Compare  results  from  selected  and  unselected  seed. 

4.  Compare  yields  from  different  lots  of  seed  of  same  variety  from 
different  sources  or  growers. 

o.  Plant  rows  respectively  with  one-eye,  two-eye,  many-eye  pieces  and 
whole  tubers.  Observe  differences  in  number  of  stems  and  tubers  per 
seed  piece  and  of  marketable  tubers. 

6.  Test   high   ridging   in   comparison   with   almost   level   culture. 

7.  Compare   results   from  untreated   and   treated   seed. 

8.  Compare  different  varieties  in  regard  to  yields  of  marketable  tubers. 


478  APPENDIX 

POTATO  EXHIBITS 

Objects  of  Exhibits. — Until  recently,  the  primary  object  of  a 
potato  exhibit  seems  to  have  been  to  gather  together  as  large  a 
collection  of  varieties,  or  so-called  varieties,  as  was  possible  in  any 
given  section.  The  premium  list  was  usually  a  long  one  and  little 
attention  was  apparently  given  to  duplication  of  varieties  under 
different  names.  Each  exhibitor  was  allowed  to  arrange  his  exhibit 
of  ])otatoes  along  with  any  other  vegetables  or  fruit  that  he  might 
be  displaying,  and  thus  it  came  about  that  potatoes  were  scattered 
here  and  there  throughout  the  exhibition  hall,  with  no  regard  to  the 
convenience  of  the  public  or  the  judges  who  had  to  pass  upon  their 
relative  merits.  Fortunately,  such  a  system  of  displaying  exhi- 
bition material,  and  of  offering  premiums  for  a  nondescript  col- 
lection of  varieties  is  rapidly  passing  away. 

The  real  object  of  holding  an  exhibition  or  show  should  be  that 
of  educating  the  public,  by  bringing  together  for  their  inspection 
and  study,  the  most  desirable  varieties,  properly  named,  and  rep- 
resenting the  best  ty{)e  specimens  of  the  variety.  The  following 
suggestions  are  offered  as  an  aid  to  such  an  accomplishment.  The 
number  or  the  quantity  of  tubers  of  each  variety  displayed  should 
be  uniform.  If  a  plate  exhibit  is  called  for,  the  number  of  tubers 
should  be  specified;  five  or  six  tubers  are  sufficient.  The  peck 
display  seems  to  have  many  adherents.  Some  potato  associations, 
such  as  the  Wisconsin  Potato  Growers'  Association,  provide  wooden 
trays  having  just  enough  depth  to  permit  of  two  layers  of  potatoes. 
All  exhibits  of  a  given  variety  should  be  assembled  together,  in  order 
to  permit  of  ease  of  study  and  comparison.  No  premiums  should 
be  offered  on  any  but  strictly  commercial  varieties,  neither  should 
a  premium  be  offered  on  two  varieties  belonging  to  the  same  class 
or  group,  as  for  example  Green  Mountain  and  Gold  Coin,  or 
Rural  New  Yorker  No.  2  and  Carman  No.  3. 

Selecting  and  Preparing  Exhibition  Tubers. — In  order  to 
intelligently  select  exhibition  tubers,  the  exhibitor  must  have  a 
clearly  defined  ideal  in  mind.  He  must  know  what  the  ideal  tuber 
shape  and  skin  color  of  the  variety  is  and  he  must  also  know  what 
size  will  be  given  preference  by  the  judges.  The  Wisconsin  Potato 
Growers  /Association  and  many  other  State  Associations  now  stipu- 
late or  suggest  a  certain  weight  of  tuber.  For  example,  Triumph 
7  ounces,  Irish  Cobbler  7  to  8  ounces,  Green  Mountain  and  Rurals 


APPENDIX  479 

9  to  10  ounces,  etc.  This  furnishes  the  grower  a  cue  as  to  the 
best  size  to  select. 

To  secure  tubers  with  an  unbroken  skin  it  is  necessary  to 
carefully  hand-dig  a  large  number  of  plants.  The  next  step  is 
to  select  a  tuber  having  the  ideal  shape,  appearance,  and  size  and 
match  it  with  others  until  a  few  more  than  the  required  number 
have  been  secured.  Tubers  intended  for  exhibit  should  be  exposed 
to  light  as  little  as  possible.  As  soon  as  selected  they  should  be 
placed  on  a  piece  of  paper  or  a  sack,  and  allowed  to  dry  oif  for  a 
few  minutes,  after  which  they  should  be  wrapped  in  paper  and 
stored  away  in  a  cool,  dark  room  until  desired  for  exhibition  pur- 
poses. In  preparing  them  for  exhibit  remove  the  wrapper  and 
brush  them  free  of  adhering  soil  with  a  soft  brush,  being  careful 
not  to  break  the  skin.  All  tubers  showing  discolorations  or  other 
imperfections  should  then  be  discarded,  and  the  remainder  again 
wrapped  and  carefully  packed  for  shipment  to  the  show.  Attention 
to  these  details  will  always  insure  attractive  show  material. 

The  Score  Card  as  an  Aid  to  Intelligent  Judging  of  Exhi- 
bits.— The  value  of  the  score  card  in  judging  potato  exhibits  is 
now  well  recognized.  Although  a  number  of  score  cards  are  in 
use  they  do  not  vary  to  any  material  extent,  they  are  all  designed 
to  serve  as  a  basis  for  the  correct  interpretation  of  certain  funda- 
mental qualities  of  the  potato  by  assigning  to  them  a  definite 
number  of  points,  the  sum  total  of  which  is  100. 

Score  Card. — The  following  score  card  is  suggested  as  a  guide 
and  aid  in  judging  potato  exhibits : 

I.  Varietal  purity. —  ( Free  from  mixture ) 20  points 

II.  Conformity  to  type. — 

1.  Shape:    correct    for   variety   and   uniform 20  points 

2.  Size:    desirable   for  variety   and   uniform 10  points 

.3.  Color :    correct    for   variety   and    uniform 5  points 

4.  Surface:  skin  and  eye  characters  normal  for  variety....  5  points 

III.  Condition  and  quality. — 

1.  Clearness,  brightness,  freedom  from  mechanical  injury..    15  points 

2.  Qiiality  of  flesh,  clear  and  firm,  not  spongy, 

free  from   streaks,  discoloration   and   hollowness 10  points 

.S.  Freedom  from  disease,  scab,  rhizoctonia,  roots 15  points 

Total 100  points 

Suggested  Descriptive  Terms  to  be  Used  in  Describing 
Potato  Varieties. — The  following  descriptive  data  were  prepared 
and  presented  at  the  Fourth  Annual  Meeting  of  the  Potato  Asso- 


480 


APPENDIX 


ciation  of  America,  by  the  Association  coimnittoe  on  varietal 
nomenclature  and  testing  of  the  })otato,  in  order  to  provide  its 
members  with  a  deiinite  outline  to  be  used  as  a  guide  in  the  descrip- 
tion of  varieties.  (A  complete  report  of  this  committee  may  be 
found  in  the  Proceedings  of  the  Fourth  Annual  Meeting  of  the 
Potato  Association :  93-94,  Nov.  9-10,  1917.  Wm.  Stuart,  Chair- 
man, A.  L.  Dacy,  E.  V.  Hardenburg,  C.  L.  Filch,  R.  Wellington, 
P.  M.  Lombard.) 

In  the  use  of  such  a  descriptive  sheet  it  is  intended  that  ail 
term^  not  applying  to  the  particular  variety  under  observation  shall 
be  crossed.  For  example,  if  the  plant  is  large,  cross  out  small 
and  medium ;  or,  if  the  tuber  is  oblong-flattened-rounded  cross  out 
all  others  on  shape,  or  else  place  a  check-mark  opposite  oblong- 
flattened-rounded. 

Suggested  Descriptive  Terms  to  be  Used 
in  Describing  Potato  Varieties 

VRACTERS. 

Seasonal  conditions;  favorable, 
unfavorable. 

Rainfall;  scanty,  normal,  exces- 
sive. 

Temperature  at  blossoming  period ; 
low,    normal,    high. 

Date  of  maturity. 

Date  harvested. 
Yield. — ^Marketable   tubers,    ....  lbs. 

Cull  tubers, lbs. 

Desirability  of  variety  for  sec- 
tion; for  home  use....;  for 
market 

Keeping  quality  of  the  variety ; 
poor,    medium,    good. 

Shipping  quality  of  the  variety; 
poor,   medium,  good. 

Eating  quality  of  the  variety; 
poor,  medium,  good. 

Resistance  to  late  blight;  none, 
little,  much. 

Resistance  to  common  scab;  none, 
little,   much. 

Resistance  to  other  diseases;  none, 
little  much. 

Observer. 


PLANT    en 

Size. — Small,  medium,  large. 

Habit. — Upright,  medium,  spreading. 

Stems. — Slender,  medium,  stout; 
little  or  much  branched;  slightly 
or  distinctly  angular;  winged  or 
smooth ;  wings  wavy  or  straight ; 
color  light  or  dark  green;  much 
or  little  tinged  with  violet. 

Leaves. — Sparse,  abundant;  small, 
medium,   large. 

Leaflets. — Narrow,  medium,  liroad ; 
smooth,  hairy;  light,  medium  or 
dark  green. 

Floicers. — None,  few,  medium,  many; 
buds  persistent  or  dropping  be- 
fore opening;  corolla  white,  rose- 
purple,  violet,  lavender  or  blue. 

Season  of  Maturity. — Very  early, 
early,  medium,  late,  very  late. 

General  Information. — Source  of 
seed. 

Date  secured. 
Amount  planted. 

Size   of   seed,  whole,   cut,    

eyes,    ozs. 

Place. — Date  planted, year, .... 

Distance    between    rows,     , 

plants, 

Area  in  square  feet. 
Soil  type. 


APPENDIX  481 

TUBEB  CHARACTERS. 

;5'i;^e._yniall,    medium,    large;    uni-   Eyes.— Few,    medium,     many;     uni- 
form, not  uniform.  formly    distributed    or    mostly 

at      apical      (bud      end;      eyes 
shallow,     medium,     deep;     eye- 
/S/tape.— Oblong— flattened— rounded.  brows     short,     medium,     long; 

Elleptical— flattened— rounded.  curved  or  straight,  curve  simple 

Oval — flattened — rounded.  or  compound. 

Roundish — flattened. 
Cubical — flattened. 

Apical  end  rounded,  blunt.  Sprouts. — Few,  medium,  many;  slen- 

Basal    end     rounded,     blunt,    de-  der,    medium,    stout;    tips    and 

pressed,  notched  and  shouldered.  jgaf    scales    are    creamy-white, 

pink,    magenta,    purple,    violet- 
^  ,         ,   .,,  .         ^   ,,      ...  blue,  or  bluish-black;  internodes 

Color  of J<l:in.-Du\l  white,  creamy-  .^^.^  ^^  magenta,  pur- 

white;   creamy-yellow;    light  or  j^^  ^j^j^^  ,^j^,     ^^.  bluish-black; 

dark    russet;    light   pink;    red;  ^^^^     ^^^l^i^  j^,^       magenta, 

magenta;   mosaic;  blue;  bluish-  ^^^^^^^^    violet-blue,    or    bluish- 

"^'^'^^-  black;      papillae     white,      pink, 

magenta,  purple,  violet-blue,  or 
Texture      of      >'^/.u».— Glossy,      dull,  bluish-black, 

smooth;        uniformly       netted; 
flaked. 

Lenticels. — Few,      medium,      many; 
prominent,   inconspicuous 

Cooking  Test. — When  the  cooking  and  table  qualities  of  differ- 
ent samples  of  potatoes  are  to  be  tested,  it  is  extremely  important 
that  each  lot  of  tubers  should  be  baked  or  l)oiled  under  as  nearly 
identical  conditions  as  possible.  The  following  method  has  been 
found  to  provide  a  uniform  cooking  test.  Select  three  or  four 
tubers  of  as  nearly  uniform  size  and  shape  as  possible;  boil  each 
lot  of  tubers  in  separate  saucepans  or  pots  of  the  same  shape  and 
size ;  begin  the  test  at  the  same  time  and  boil  them  alike  until  done. 
In  the  baking  tests  select  the  tubers  in  the  same  manner,  but  place 
each  lot  in  the  same  oven.  Maintain  the  oven  temperature  as 
nearly  as  may  be  at  380  degrees  F.  until  they  are  done.  On  re- 
moval from  the  oven,  break  or  puncture  the  skin  so  as  to  allow  the 
steam  to  escape.  Remove  the  skin  from  all  but  one  baked  or 
boiled  potato  as  quickly  as  possible  after  removal  from  pot  or  oven, 
and  mash  the  flesh  with  a  fork  or  potato  masher  to  determine  the 
fineness  or  grain  of  the  flesh,  its  color  and  general  appearance, 
and  its  pleasantness  of  taste,  as  determined  by  actual  test  of  its 
eating  qualities.     This  test  should  be  made  without  the  addition 

31 


482  APPENDIX 

of  butter  or  seasoning  of  any  sort,  in  order  to  catch  the  true  edible 
qualities  of  the  tubers  studied.  Each  remaining  tuber  should  be 
set  aside  and  allowed  to  get  cold,  after  Avhich  it  is  to  be  re-warmed 
for  the  })urpose  of  ascertaining  to  what  degree  the  flesh  retains 
its  color  and  mealiness.  The  flesh  of  some  varieties  turns  undesira- 
bly dark  when  re-warmed. 

Points  to  be  considered  in  judging  the  table  qualities  of  pota- 
toes are  ease  and  uniformity  of  cooking;  skin  and  flesh  intact 
or  nearly  so  when  boiled ;  texture  of  flesh ;  character  of  grain  when 
mashed;  color  of  flesh;  flavor.  The  following  ratings  have  been 
found  fairly  satisfactory : 

Ease  of  cooking 5  points 

Uniformity  of  cooking 10  points 

Skin  and  flesh  intact  when  boiled  * 10  points 

Texture  of  flesh 15  points 

Grain   when    mashed 15  points 

Whiteness   of  mashed   flesh 15  points 

Flavor .30  points 

Total 100  points 

POTATO  TRIPS 

Trips  to  potato  fields  and  elsewhere  may  be  planned  with 
profit.  Students  should  be  given  'an  outline  of  the  main  features 
to  be  studied  on  each  trip.  They  should  prepare  for  the  trip  by 
reviewing  these  points.  Notes  should  be  made  during  the  trip  from 
which  to  write  an  accomit  of  the  observations  and  lessons  learned. 

1.  Visit  fields  for  practice  in  choosing  good  potato  soils. 

2.  Go  to  seed  storage  places  and  retail  seed  stores  to  study  varie- 

ties, methods  of  handling,  and  protection  and  prices. 

3.  When  large  growers  or  others  are  preparing  the  soil  for  pota- 

toes, visit  the  fields  and  take  notes  on  methods. 

4.  Such  ]ilaces  should  also  be  visited  when  seed  potatoes  are  being 

treated  for  scab  and  rhizoctonia,  cut  for  planting,  green- 
ing, etc. 

5.  Study  planting  machines  of  several  kinds;  if  possible,  when  in 

actual  operation  in  fields. 

6.  Study  pre-germination  tillage  and  after-tillage  in  potato  fields. 

*  jVo^e. — Waste,  through  rupturing  of  skin  and  sloughing  away  of 
flesh,  may  be  entirely  avoided  by  the  use  of  a  steam  cooker. 


APPENDIX  483 

7.  Where  Bordeaux  mixture  and  other  spray  materials  are  being 

made  for  field  work,  make  studies  of  methods  and  results. 
Study  methods  of  spraying  and  dusting.  If  there  are  out- 
breaks of  blight  or  other  troubles  examine  them  carefully. 

8.  At  harvest  time,  study  methods  of  harvesting,  picking,  hand- 

ling, sizing,  grading  and  record  keeping. 

9.  Take  trips  to  study  store  houses  under  construction  or  when 

in  use.  Draw  their  plans  and  make  estimates  of  cost  for 
material  and  labor.     Visit  cold-storage  plants  if  possible. 

10,  Study  operations  at  shipping  points;  grading,  classifying,  va- 

rieties, summer  cars,  winter  cars,  cooperative  endeavors, 
record  keeping,  crediting. 

11.  If  any  kind  of  manufacturing  plant  using  potatoes  is  near 

visit  that  and  study  methods,  products  and  by-products. 
13.  Visit  large  retail  and  wholesale  markets.  Study  good  and 
bad  handling,  diseases,  containers,  grades,  sizes,  varieties, 
prices.  Secure  specimens  and  compare  in  knife  tests: 
smooth  to  pare  thin,  flesh  white  or  true  to  type,  sound 
and  rather  dry,  not  hollow,  cortical  layer  thick,  central 
areas  small,  not  watery. 


APPENDIX 


485 


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492 


APPENDIX 


Yearly  and  average  acreage  and  production  by  Slates  for  the  years  1915  to  1919  inclusive* 


State 

Year 

Acres 

Total 
bushels 

Average 

bu.  per 

acre 

Farm 
price 
per  bu. 
Dec.  1 

1915 
1916 
1917 
1918 
1919 

355,000 
320,000 
400,000 
380,000 
363,000 

22,010,000 
22,400,000 
38,000,000 
37,240,000 
39,567,000 

62. 
70. 
95. 
98. 
109. 

$  .82 
1.58 
1.30 

1.22 
1.45 

Average. 

363,600 

31,843,400 

87.6 

Minnesota 

1915 
1916 
1917 
1918 
1919 

285,000 
280,000 
300,000 
312,000 
300,000 

30,210,000 
16,800,000 
33,600,000 
32,760,000 
26,100,000 

106. 

60. 

112. 

105. 

87. 

.39 

1.30 

91 

.75 
1.53 

Average 

295,400 

27,894,000 

94.4 

Wisconsin 

1915 
1916 
1917 
1918 
1919 

298,000 
290,000 
307,000 
304,000 
300,000 

25,926,000 
13,630,000 
34,998,000 
33,440,000 
28,200,000 

87. 

47. 
114. 
110. 

94. 

.45 

1.47 

.90 

.80 

1.40 

Average 

299,800 

27,238,000 

90.9 

Michigan 

1915 
1916 
1917 
1918 
1919 

355,000 
320,000 
378,000 
340,000 
326,000 

20,945,000 
15,360,000 
35,910,000 
28,560,000 
28,688,000 

59. 
48. 
95. 
84. 

88. 

.56 
1.60 
1  05 

.89 
1.35 

Average 

343,800 

25,892,000 

75.3 

1915 
1916 
1917 
1918 
1919 

142,000 
125,000 
150,000 
112,000 
102,000 

25,418,000 
25,500,000 
18,750,000 
22,400,000 
24,480,000 

179. 
204. 
125. 
200. 
240. 

.70 

1.42 
1  30 

1.20 
1.40 

Average 

126,200 

23,309,600 

184.7 

Pennsylvania 

1915 
1916 
1917 
1918 
1919 

280,000 
272,000 
321,000 
275,000 
254,000 

20,160,000 
19,040,000 
29,532,000 
22,000,000 
25,400,000 

72. 
70. 
92. 
80. 
100. 

.75 
1.48 
1  35 

1.51 
1.54 

Average 

280,400 

23,226,000 

82.8 

♦The  data  in  this  table  were  taken  from  the  December  (1916  and  1910)  Monthly  Crop  Re- 
port of  the  Bureau  of  Crop  Estimates  of  the  U.  S.  Department  of  Agriculture.  These  data  do 
not  in  all  cases  coincide  with  those  given  in  the  Department  Yearbook,  as  they  represent  re- 
vised estimates  based  on  more  complete  information. 


APPENDIX 


493 


State 

1 

Year 

Acres 

Total 
bushels 

Average 

bu.  per 

acre 

Farm 
price 
per  bu. 
Dec.  1 

1915 
1916 
1917 
1918 
1919 

140,000 
125,000 
175,000 
135,000 
121,000 

17,.500,000 
16,2.50,000 
17,325,000 
12,690,000 
11,495,000 

125. 
130. 

99. 

94. 

95. 

$  .61 
1.37 
1.25 

1.20 
1.57 

Average 

139,200 

15,052,000 

108.1 

California        

1915 
1916 
1917 
1918 
1919 

78,000 
75,000 
105,000 
90,000 
88,000 

10,140,000 
10,575,000 
15,225,000 
12,870,000 
11,352,000 

130. 
141. 
145. 
143. 
129. 

.75 
1.40 
1.50 
1.20 

1.71 

Averace 

87,200 

12,032,400 

137.9 

Ohio 

1915 
1916 
1917 
1918 
1919 

153,000 
140,000 
160,000 
160,000 
150,000 

12,.546,000 
6,300,000 
16,000,000 
11,040,000 
9,300,000 

82. 
45. 
100. 
69. 
62. 

.70 
1.82 
1.43 

1.50 
1.92 

152,600 

11,037,200 

72.3 

1915 
1916 
1917 
1918 
1919 

93,000 
85,000 
98,000 
117,000 
110,000 

12,090,000 
10,370,000 
11,172,000 
10,764,000 
10,560,000 

130. 
122. 
114. 

92. 
96. 

.75 
1.55 
1.41 

1.70 
1.69 

100,600 

10,991,200 

109.2 

Illinois 

1915 
1916 
1917 
1918 
1919 

126,000 
125,000 
150,000 
160,000 
155,000 

13,860,000 

7,250,000 

13,500,000 

11,520,000 

8,060,000 

110. 

58. 
90. 
72. 
52. 

.59 
1.79 
1.52 

1.48 
1.96 

Average. 

143,200 

10,838,000 

75.7 

Colorado 

1915 
1916 
1917 
1918 
1919 

53,000 
50,000 
80,000 
99,000 
92,000 

7,155,000 

6,900,000 

12,800,000 

15,840,000 

11,040,000 

135. 
138. 
160. 
160. 
120. 

.55 

1.35 

.91 

.99 
1.70 

Average.  . 

74,800 

10,747,000 

143.7 

494 


APPENDIX 


State 

Year 

Acres 

Total 
bushels 

Average 

bu.   per 

acre 

Farm 
price 
per  bu. 
Dec.  1 

1915 
1916 
1917 
1918 
1919 

110,000 
105,000 
147,000 
121,000 
115,000 

11,550,000 

7,665,000 

12,495,000 

10,406,000 

6,325,000 

105. 

73. 
85. 
86. 
55. 

$  .42 
1.50 
1.07 

1.18 
1.90 

119,600 

9,688,200 

81.0 

Iowa 

1915 
1916 
1917 
1918 
1919 

120,000 
115,000 
138,000 
128,000 
115,000 

12,600,000 
4,830,000 

13,110,000 
9,216,000 
4,945,000 

105. 
42. 
95. 

72. 
43. 

.54 
1.75 
1.31 

1.33 
1.92 

Averaffc                   

123,200 

8,940,200 

72.5 

1915 
1916 
1917 
1918 
1919 

61,000 
60,000 
79,000 
63,000 
58,000 

8,235,000 
9,900,000 
9,875,000 
8,316,000 
7,250,000 

135. 
165. 
125. 
132. 
125. 

.53 
.98 
.92 

1.01 
1.45 

Average.                              . .  .  . 

64,200 

8,715,200 

135.8 

1915 
1916 
1917 
1918 
1919 

90,000 
91,000 
109,000 
114,000 
110,000 

8,820,000 
5,460,000 
9,483,000 
6,954,000 
8,250,000 

98. 
60. 
87. 
61. 
75. 

.60 
1.80 
1.37 

1.53 
1.84 

Average                               .    .  . 

102,800 

7,793,400 

75.8 

North  Dakota 

1915 
1916 
1917 
1918 
1919 

80,000 
75,000 
90,000 
92,000 
90,000 

7,200,000 
6,975,000 
3,870,000 
9,108,000 
5,670,000 

90. 
93. 
43. 
99. 
63. 

.41 
1.15 
1.30 

.73 
1.60 

Average 

85,400 

6,564,600 

76.9 

South  Dakota 

1915 
1916 
1917 
1918 
1919 

68,000 
65,000 
80,000 
95,000 
90,000 

7,820,000 
4,290,000 
7,200,000 
8,645,000 
4,500,000 

115. 
66. 
90. 
91. 
50. 

.35 
1.37 
1.11 

.93 
1.90 

Average. 

79,600 

6,491,000 

81.5 

APPENDIX 


495 


state 

Year 

Acres 

Total 
bushels 

Average 

bu.   per 

acre 

Farm 
price 

per  bu. 

Dec.  1 

1915 
1916 
1917 
1918 
1919 

75,000 

74,000 

92,000 

108,000 

100,000 

7,125,000 
3,256,000 
8,464,000 
8,640,000 
4,400,000 

95. 
44. 
92. 
80. 
44. 

$    .56 

1.77 
1.39 

1.35 
1.95 

Average ...                         ... 

89,800 

6,377,000 

71.0 

Oregon 

1915 
1916 
1917 
1918 
1919 

48,000 
55,000 
75,000 
50,000 
45,000 

5,520,000 
8,250,000 
8,100,000 
5,500,000 
4,230,000 

115. 
150. 
108. 
110. 
94. 

.60 
.90 
.80 

1.00 
1.50 

54,600 

6,320,000 

115.8 

Kentucky 

1915 
1916 
1917 
1918 
1919 

'    51,000 
49,000 
70,000 
75,000 
72,000 

6,426,000 
4,116,000 
6,720,000 
5,625,000 
5,040,000 

126. 
84. 
96. 
75. 
70. 

.55 
1.42 
1  40 

1.65 
2.10 

Average.                              .    . . 

63,400 

5,585,400 

88.1 

West  Virginia 

1915 
1916 
1917 
1918 
1919 

50,000 
48,000 
55,000 
55,000 
57,000 

5,850,000 
4,224,000 
6,325,000 
4,785,000 
5,130,000 

117. 

88. 
115. 
87. 
90. 

.65 
1.58 
1  32 

1.60 
1.75 

53,000 

5,262,800 

99.3 

1915 
1916 
1917 
1918 
1919 

39,000 
39,000 
57,000 
50,000 
47,000 

6,045,000 
4,875,000 
5,415,000 
6,750,000 
2,820,000 

155. 
125. 

95. 
135. 

60. 

.50 
1.20 
1  02 

.80 
1.60 

Average 

46,400 

5,181,000 

111.7 

Idaho 

1915 
1916 
1917 
1918 
1919 

28,000 
27,000 
39,000 
34,000 
36,000 

3,500,000 
4,050,000 
6,084,000 
6,290,000 
5,400,000 

125. 
150. 
156. 
185. 
150. 

.56 

1.27 

79 

.81 
1.51 

Average 

32,800 

5,064.800 

154.4 

490 


APPENDIX 


.state 

Year 

Acres 

Total 
bushels 

Average 

bu.    per 

acre 

Farm 
price 

per  bu. 

Dec.  1 

Kansas 

1915 
1916 
1917 
1918 
1919 

71,000 
70,000 
78,000 
80,000 
68,000 

5,893,000 
4,970,000 
4,446,000 
4,240,000 
5,168,000 

83. 
71. 
57. 
53. 
76. 

$  .74 
1.65 
1  52 

1.44 
1.90 

Average 

73,400 

4,943.400 

67.3 

Maryland 

1915 
1916 
1917 
1918 
1919 

44,000 
43,000 
60,000 
53,000 
55,000 

4,268,000 
4,085,000 
6,000,000 
4,240,000 
5,170,000 

97. 
95. 
100. 
80. 
94. 

.62 
1.33 
1  19 

1.20 
1.30 

51,000 

4,752,600 

93.2 

North  Carolina 

1915 
1916 
1917 
1918 
1919 

35,000 
34,000 
50,000 
65,000 
58,000 

3,150,000 
3,230,000 
4,500,000 
6,175,000 
4,930,000 

90. 
95. 
90. 
95. 

85. 

.73 
1.40 
1  43 

1.35 
1.63 

Average 

48,400 

4,397,000 

90.8 

Tennessee 

1915 
1916 
1917 
1918 
1919 

36,000 
36,000 
52,000 
50,000 
48,000 

3,168,000 
2,952,000 
4,888,000 
3,500,000 
3,120,000 

88. 
82. 
94. 
70. 
65. 

.63 
1.49 
1  26 

1.65 
1.72 

44,400 

3,525,600 

79.4 

Massachusetts 

1915 
1916 
1917 
1918 
1919 

26,000 
25,000 
38,000 
34,000 
33,000 

3,120,000 
2,275,000 
4,370,000 
4,522,000 
2,970,000 

120. 

91. 
115. 
133. 

90. 

.94 
1.75 
1.75 
1.70 
1.90 

Average 

31,200 

3,451,400 

110.6 

Wvoming 

1915 
1916 
1917 
1918 
1919 

17,000 
18,000 
32,000 
30,000 
33,000 

2,550,000 
2,340,000 
4,960,000 
4,500,000 
2,640,000 

150. 
130. 
155. 
150. 
80. 

.60 
1.28 
1  04 

.85 
1.90 

Average 

26,000 

3,398,000 

130.7 

APPENDIX 


497 


state 

Year 

Acres 

Total 
bushels 

Average 
bu.   per 

Farm 
price 

per  bu. 

Dec.  1 

Utah 

1915 
1916 
1917 
1918 
1919 

20,000 
20,000 
23,000 
20,000 
17,000 

2,500,000 
3,600,000 
4,347,000 
3,600,000 
2,397,000 

125. 
180. 
189. 
180. 
141. 

$   .63 
1.30 

.78 

.97 
1.37 

Average 

20,000 

3,288,800 

164.4 

1915 
1916 
1917 
1918 
1919 

24,000 
23,600 
30,000 
28,000 
25,000 

2,592,000 
2,576,000 
3,000,000 
3,640,000 
3,125,000 

108. 
112. 
100. 
130. 
125. 

.81 
1.39 
1.40 

1.38 
1.57 

Average 

26,000 

2,986,600 

114.9 

1915 
1916 
1917 
1918 
1919 

20,000 
20,000 
41,000 
60,000 
44,000  ^ 

1,600,000 
1,800,000 
2,952,000 
4,800,000 
3,520,000 

80. 
90. 
72. 
80.' 
80. 

.90 
1.69 

1.82 

1.81 
2.15 

37,000 

2,934,400 

79.3 

Texas 

1915 
1916 
1917 
1918 
1919 

42,000 
40,000 
46,000 
60,000 
52,000 

2,730,000 
2,000,000 
2,760,000 
3,300,000 
3,796,000 

65. 
50. 
60. 
55. 
73. 

1.05 
1.90 
2.10 

2.00 
2.10 

Average                               .    . 

48,000 

2,917,200 

60.8 

1915 
1916 
1917 
1918 
1919 

28,000 
25,000 
46,000 
48,000 
41,000 

2,520,000 
1,625,000 
3,680,000 
2,400,000 
3,321,000 

90. 
65. 
SO. 
.50. 
81. 

.76 
1.90 
1.57 

1.84 
2.05 

37,600 

2,709,200 

72.1 

1915 
1916 
1917 
1918 
1919 

35,000 
34,000 
36,000 
50,000 
44,000 

2,975,000 
1,802,000 
2,484,000 
1,700,000 
3,520,000 

85. 
53. 
09. 
34. 
80. 

.84 
1.95 
1.80 

1.95 
2.05 

"  39,800 

2,496,200 

62.7 

32 


498 


APPENDIX 


State 

Year 

Acres 

Total 
bushels 

Average 

bu.  per 

acre 

Farm 
price 

per  bu. 

Dec.  1 

Connecticut 

1915 
1916 
1917 
1918 
1919 

24,000 
22,000 
27,000 
25,000 
24,000 

2,280,000 
2,090,000 
2,970,000 
2,375,000 
1,680,000 

95. 
95. 
110. 
95. 
70. 

S   .96 
1.75 
1  64 

1.65 
1.95 

Average 

24,400 

2,279,000 

93.4 

New  Hampshire 

1915 
1916 
1917 
1918 
1919 

16,000 
15,000 
22,000 
21,000 
20,000 

1,520,000 
1,800,000 
2,354,000 
2,940,000 
2,400,000 

95. 
120. 
107. 
140. 
120. 

.95 
1.66 
1.67 

1.45 
1.75 

Average. 

18,800 

2,202,800 

117.2 

Louisiana 

1915 
1916 
1917 
1918 
1919 

28,000 
25,000 
25,000 
55,000 
25,000 

1,428,000 
1,625,000 
1,600,000 
4,345,000 
1,600,000 

51. 
65. 
64. 
79. 
64. 

.95 
1.67 
1.84 

1.50 
2.20 

Average 

31,600 

2,119,600 

67.1 

Nevada 

1915 
1916 
1917 
1918 
1919 

13,000 
14,000 
11,000 
9,000 
6,000 

2,236,000 
2,660,000 
2,277,000 
1,539,000 
900,000 

172. 
190. 
207. 
171. 
150. 

.70 
1.30 
1  20 

1.23 
1.50 

Average. 

10,600 

1,922,400 

181.4 

Florida 

1915 
1916 
1917 
1918 
1919 

12,000 
15,000 
25,000 
35,000 
24,000 

960,000 
1,110,000 
2,275,000 
3,500,000 
1,824,000 

80. 
74. 
91. 
100. 
76. 

1.15 
2.00 
2  05 

2.00 
2.10 

Average. 

22,200 

1,933,800 

87.1 

South  Carohna 

1915 
1916 
1917 
1918 
1919 

11,000 
10,000 
20,000 
28,000 
27,000 

'880,000 

750,000 

1,920,000 

2,856,000 

2,295,000 

80. 

75. 

96. 

102. 

85. 

1.15 
1.75 
2  10 

1.93 
2.00 

Average.  .    . 

19,200 

1,740,200 

90.6 

APPENDIX 


499 


state 

Year 

Acres 

Total 
bushels 

Average 

bu.   per 

acre 

Farm 
price 

per  bu. 

Dec.  1 

1915 
1916 
1917 
1918 
1919 

16,000 
15,000 
19,000 
23,000 
23,000 

1,040,000 
900,000 
1,596,000 
1,610,000 
1,610,000 

65. 
60. 
84. 
70. 
70. 

$  .99 
1.75 
1  95 

1.85 
2.17 

Average 

19,200 

1,351,200 

70.4 

1915 
1916 
1917 
1918 
1919 

13,000 
12,000 
15,000 
20,000 
18,000 

1,170,000 
780,000 
1,170,000 
1,600,000 
1,530,000 

90. 
65. 

78. 
80. 
85. 

.84 
1.60 
1.68 

1.65 
1.85 

15,600 

1,250,000 

80. 

1915 
1916 
1917 
1918 
1919 

11,000 
10,000 
13,000 
12,000 
11,000 

1,045,000 

900,000 

1,235,000 

1,044,000 

913,000 

95. 
90. 
95. 

87. 
83. 

.75 
1.25 
1.30 

1.40 
1.25 

Average 

11,400 

1,027,400 

90.1 

New  Mexico 

1915 
1916 
1917 
1918 
1919 

8,000 
8,000 
11,000 
10,000 
11,000 

800,000 

816,000 

1,276,000 

1,000,000 

495,000 

100. 
102. 
116. 
100. 
45. 

.95 
1.75 
1  65 

1.60 
1.90 

9,600 

877,400 

91.4 

Rhode  Island 

1915 
1916 
1917 
1918 
1919 

5,000 
5,000 
5,000 
5,000 
5,000 

550,000 
370,000 
675,000 
650,000 
425,000 

110. 
74. 
135. 
130. 

85. 

.92 
1.85 
1.75 

1.73 
1.80 

Average .... 

5,000 

534,000 

106.8 

Arizona    

1915 
1916 
1917 
1918 
1919 

1,000 
1,000 
4,000 
5,000 
5,000 

95,000 
115,000 
420,000 
425,000 
350,000 

95. 
115. 
105. 

85. 

70. 

1.00 
1.80 
1.50 

2.05 
1.95 

Average 

3,200 

281,000 

87.8 

500 


APPENDIX 


Canadian  potato  acrea>je ;  yield  and  price  per  bushel  by  Provinces  for  the  years 
1912-191S  inclusive. 


Province 

Year 

Acreage 

Total  yield 
bu. 

Av.  bu. 
per  acre 

Av. 

price 

per  bu. 

Prince  Edward  Island 

1912 
1913 
1914 
1915 
1916 
1917 
1918 

33,000 
32,000 
32,000 
31,000 
31,000 
35,000 
31,543 

6,741,000 
6,219,000 
6,806,000 
3,558,000 
6,386,000 
6,125,000 
5,362,300 

206.4 

194.3 
212.7 
114.8 
206.0 
175.0 
170.0 

$0.26 
.28 
.23 
.46 
.52 
.75 
.63 

1912 
1913 
1914 
1915 
1916 
1917 
1918 

32,000 
32,000 
32,.500 
34,000 
34,000 
41,000 
51,250 

9,447,000 
5,369,000 
7,165,000 
4,759,000 
6,935,000 
7,173,000 
9,942,500 

298.6 
167.8 
220.5 
141.2 
201.0 
175.0 
194.0 

.47 
.52 
.49 

.58 

.69 
.92 
.93 

New  Brunswick    

1912 
1913 
1914 
1915 
1916 
1917 
1918 

43,000 
43,500 
43,900 
40,000 
39,000 
46,000 
57,272 

7,558,000 
10,629,000 
10,.534,000 
5,772,000 
7,488,000 
6,891,000 
9,077,600 

174.6 
244.4 
239.9 
144.3 
192.C 
149.8 
1.58.5 

.42 
.44 
.40 
.64 

.84 
1.13 
1.00 

Quebec. . .   .      

1912 
1913 
1914 
1915 
1916 
1917 
1918 

116,000 
116,000 
115,000 
117,000 
112,000 
226,917 
264,871 

15,945,000 
20,504,000 
21,811,000 
17,510,000 
14,672,000 
18,158,000 
38,936,000 

137.1 
176.8 
189.7 
149.7 
131.0 
80.0 
147.0 

.35 
.46 
.42 
.55 

.97 

1.38 

.98 

Ontario  .    .   ... 

1912 
1913 
1914 
1915 
1916 
1917 
1918 

158,000 
152,000 
154,000 
155,000 
133,000 
142,000 
166,203 

22,690,000 
18,105,000 
25,772,000 
14,362,000 
8,113,000 
18,981,000 
20,443,000 

143.9 
119.1 
167.4 
92.7 
61.0 
133.8 
123.0 

.59 
.65 
.47 
.76 

1.28 
1.00 
1.26 

Manitoba  . . . 

1912 
1913 
1914 
1915 
1916 
1917 
1918 

27,000 
26,000 
26,900 
28,000 
32,000 
34,400 
45,000 

6,182,000 
5,120,000 
3,172,000 
3,104,000 
4,709,000 
3,643,000 
8,325,000 

231.6 
196.9 
117.9 
109.7 
170.0 
106.0 
185.0 

.35 
.36 
.72 
.54 

.61 

.76 
.56 

APPENDIX 


501 


Province 

Year 

Acreage 

Total  yield 
bu. 

Av.  bu. 
per  acre 

Av. 

price 

per  bu. 

Saskatchewan 

1912 
1913 
1914 
1915 
1916 
1917 
1918 

31,000 
31,000 
30,600 
30,300 
47,000 
67,700 
59,793 

6,552,000 
5,138,000 
4,085,000 
4,428,000 
7,319,000 
9,010,000 
6,950,900 

209.7 
165.7 
133.5 
146.2 
176.0 
133.0 
116.3 

$  .40 

.47 

1.05 

.49 

.62 
.85 
.96 

Alberta  

1912 
1913 
1914 
1915 
1916 
1917 
1918 

27,000 
26,000 
26,300 
27,300 
29,000 
48,917 
44,247 

5,775,000 
4,350,000 
3,652,000 
5,155,000 
4,783,000 
7,409,000 
3,119,400 

211.6 
167.3 
138.9 
188.8 
177.0 
151.5 
70.5 

.39 
.39' 
.65 
.33 

.53 

.76 

1.11 

British  Cohimbia 

1912 
1913 
1914 
1915 
1916 
1917 
1918 

17,000 
15,000 
14,700 
16,000 
15,000 
15,024 
15,013 

3,995,000 
3,110,000 
2,675,000 
3,956,000 
2,892,000 
2,502,000 
3,423,000 

233.2 
207.3 
182.0 
247.3 
189.0 
166.5 
228.0 

.49 
.66 
.78 
.45 

.70 
.69 
.97 

^'Zl? 


INDEX 


Absorbents    to   use    on    freshly    cut 

seed,  60 
Abundance  and  viability  of  pollen, 

395 
Acre  yields  by  states  and  provinces, 

'  495-501 
Actinomyces  scabies  (common  scab) , 

264 
Advantages    of    one-    and    two-man 

planter,  66 
Advantages  of  pitting  potatoes,  225 
Ai'ration  of  storage  house,  210 
Affinity    and    non-affinity   of   pollen 

and  ovules,  406 
Air  circulation  in  the  storage  house, 

211 
Air  conduits  in  the  storage  house, 

212 
Alabama  potato  production.   111 
Alberta  Province,  yearly  potato  pro- 
duction, 501 
Alcohol  production,  358 
Alexander,    0.    H.,   potato    breeding 

work,  388 
Alfalfa  analyses,  29 
Alfalfa  in  4-year  rotation,  42 
Alfalfa  sod,  24 
Altitude  effects,  15 
American  potato  breeders,  385 
American  potato  mania,  393 
Ammonia    system    of    refrigeration, 

236 
Amount  of  commercial  fertilizer  to 

apply,  32 
Amount  of  plant  food  needed,  28 
Amount  of  seed  to  use,  62 
Ample    storage    facilities    desirable, 

203 
Anatomical    structure    of    potato 

tuber,  367 
Anderson's  method  of  selection,  415 
Animal  parasites,  291 
Annual  crop  after  potatoes,  40 
App's  cost  data,  160 
Appendix,  475 
Appleman,    C.   0.,   low   temperature 

changes,  209 
Application    of    Bordeaux    mixture, 

330 


Application     of     commercial     ferti- 
lizers, 33 
Application  of  irrigation  water,  84 
Arizona  potato  production,   150 
Arkansas  potato  production,   115 
Aroostook  Co.,  Me.,  production,  123 
Aroostook  Co.,  Me.,  type  of  storage 

house,  234 
Arsenate    of    lead,    how    made    and 

used,  337    , 
Arsenical  injury,  284 
Arsenite  of  zinc,  338 
Arsenoids,    white,   pink,   and    green, 

338 
Arthur,  J.  C,  formalin  treatment  of 

tuber,  333 
Arthur,  J.  C,  moisture  requirements 

of  plants,  20 
Arthur,    J.    C,    morphology    of    the 

tuber,  365 
Artificial  cross-pollination,  399 
Artificially    refrigerated   storage 

houses,  236 
Authorities  differ  on  origin   of  the 

potato,  378 
Average  acre  production  of  six  lead- 
ing states,   121 
Average  acre  yield  by  states,  8,  9 
Average   annual   production    in   the 

South,   92 
Average  production  by  states,  7-9 
Average    production    of    three    geo- 
graphical sections,  92 

Bacterial  diseases,  248 

Bacterial  wilt,  274 

Bad   and   good   Bordeaux   mixtures, 

326 
Bad  handling  of  seed,  69 
Bagging  potato  flowers,  400 
Bailey,  L.  H.,  early  potato  culture 

in  America,  381 
Baker,  J.  G.,  classification  of  tuber- 
bearing  Solanums,  364 
Ball,  E.  D.,  potato  leafhopper,  315 
Ballou,  production  centres  in  Ohio, 
Ballou's  classification  system,  438 
135 

503 


504 


INDEX 


Bauhin's  description  of  the  potato, 
372 

Beaufort,   S.   C,   cultural   practices, 
83 

Beecher,  H.  W.,  comment  on  Good- 
rich's work,  386 

Benefits    from    germinating    tubers 
before  planting,  53 

Berthault,  P.,  tuber  variations,  420 

Berthon,  H.,  potato  tuber  moth,  304 

Best  storage  temperature,  208 

Bird,  R.  M.,  Preparation  of  dry  Bor- 
deaux mixture,  331 

Bird  and  Grimes,  suitable  cars  and 
proper  loading,  197 

Bitter,    G.,    classiiication    of    tuber- 
bearing  Solanums,  364 

Blackfoot    and    Twin    Falls,    Idaho, 
districts,  149 

Black-leaf,  40,  339 

Blackleg,  271 

Black  scurf   (Pvhizoctonia),  262 

Blister  beetles,  298 

Blossoming  of  potatoes  in  Maine,  125 

Bolley,  H.  L.,  soil  sanitation,  38 

Bordeaux  mixture,  324 

Bordeaux  paste,  331 

Bordeaux  powder,  331 

Botany  of  the  potato,  364 

Bovee's    potato    contributions,    390 

Breeding  and  selection  defined,  384 

Bresee's  potato-breeding  work,  386 

Briggs  and  Shantz,  moisture  require- 
ments, 20 

Brine  system  of  refrigeration,  237 

British    Columbia's    yearly    produc- 
tion, 501 

British  potato  breeders,  392 

Brittain,  W.  N.,  potato  stalk  borer, 
299 

Britton,  W.  E.,  Colorado  beetle,  291 
cutworms,  301 
four-lined   leaf-bug,  314 
kerosene  emulsion,  340 

Brownell's  potato-breeding  work,  388 

Bug-death,   332 

Burbank  group,  458 

Burbank  seedling,  458 

Burbank's  potato-breeding  work,  388 

Burlap  sack,  seed  potato  container, 
193 

Burley,   Idaho,  potato   district,    149 

liushel  cost  of  storage,  239 

Business  principles,  156 

Butler's  conclusions  on  aiiration,  212 


Butler's  studies  on  relation  of  stor- 
age temperatures  to  loss  in 
tuber  weight,  218 

Byar's,  L.  P.,  eelworm,  319 

Calcium  arsenate,  337 

Caldwell,  Idaho  potato  district,  149 

California     commercial     production 

centres,  152 
California  crop,  harvesting  of,  152 
California  "tule"  land  district,  152 
Canada's  potato  acreage  and  yields, 

11,  12 
Canada's    production    by    provinces, 

11,  500 
Carbon  bisulfid,  309 
Careful  harvesting  of  croj),  171 
Caribou  loam  soil,  123 
Carman's  potato-breeding  work,  389 
Carpenter,  C.  W.,  fusaria  sp.,  257 
Carriere's  observations  on  variation, 

416 
Causes  of  poor  stands,  69 
Certified  seed  potatoes,  49 
Character  of  mosaic  disease,  278 
Character  of  storage  house,  225 
Chemical  elements  in  plants,  27 
Chute    method    of    filling    storage 

house,  233 
Cieca's  observations  on  the  potato, 

369 
Clark's  potato-breeding  Avork,  392 
Classification     and     description     of 

varieties,  435 
Classification  key   (Stuart's),  440 
Classification  of  flowering  habits  of 

varieties,  394 
Classification   of   insect  and  animal 

pests,  290 
Classification  of  tuber-l)earing  sola- 
nums, 364 
Climatic     conditions     in     Aroostook 

Co.,  Me.,  124 
Clover  analysis,  29 
Clover  sods,  25 

Clusius,  C.  description  of  S.  tubero- 
sum, 371 
Color  of  stamens  of  flowers,  397 
Colorado     commercial     potato     dis- 
tricts,  143 
Colorado  construction   costs,  239 
Colorado  potato  beetle,  291 
Commercial  fertilizer  formulae,  32 
Commercial  fertilizers  and  their  use, 
31 


INDEX 


505 


Commercial  production  centres  in 
South,  96 

Commercially  prepared  Bordeaux 
powder,  331 

Common  scab,  264 

Comparison  of  one-  and  two-man 
planter,  66 

Comparison  of  second  crop  practices, 
105 

Comparison  of  WoUny's  and  De- 
naifife's  data,  217 

Conclusions  on  storage  temperature, 
209 

Constituents  of  the  potato,  348 

Construction  of  Aroostook  Co.,  Me., 
type  of  storage  house,  234 

Construction  of  dugout  storage 
house,  226 

Construction  of  insulated  wooden 
storage  house,  233 

Consumption  of  potato  crop,  360 

Containers  for  potatoes  and  their 
cost,    102 

Continuous  cropping  with  potatoes, 
41 

Control  measures  for  fusarium  wilt, 
256 

Control  measures  for  late  blight, 
254 

Control  measures  for  white  grubs, 
303 

Cooking  test,  4S1 

Coon,  G.  H.,  early  blight,  250 

Cooper,  M.,  brine  system  of  refriger- 
ation, 237 

Cooper,  M.,  humidity  of  air  in  stor- 
age house,  210 

Cooper,  M.,  storage  temperature,  208 

Cooperative  marketing  organiza- 
tions,  199 

Corbett,  L.  C,  temperature  of  stor- 
age house,  208 

Corrosive  sublimate  treatment,  332 

Cost  factors  in  potato  production, 
156 

Cost  of  picking  potatoes,  176 

Cost  of  storage  per  bushel,  239 

Cost  per  acre,  155 

Cost  per  bushel,  155 

Condon  and  Bussard's  division  of 
tuber,  367 

Coy,  E.  L.,  potato-breeding  work, 
389 

Craine,  Thos.,  potato-breeding  work, 
390 


Critical  period  in  the  potato  plant's 

growth,  16 
Crop  rotation,  38 
Cultural  care  of  the  growing  crop, 

74 
Cultural   practices    in    Long   Island 

and  New  Jersey,  130 
Cultural  practices  in  Michigan,  Wis- 
consin and  Minnesota,   138 
Cultural  practices   in  N.   D.,   S.   D., 

Neb.,  and  Kan.,  140 
Cultural    practices    in    second    crop 

production,  103 
Cultural  practices   in  Western  New 

York  and  Pa.,  131 
Curly  dwarf,  283 
Cutting  the  seed,  58 

Dacv,  A.  L.,  potato  culture  in  W. 
Va.,  117 

Danger  of  cross-pollination,  401 

Date  of  harvesting  the  potato  crop, 
166 

Date  of  planting  in  Arizona,  150 

Date  of  planting  in  Nevada,  150 

Date  of  planting  in  Western  New 
York,  131 

Date  of  planting  the  three  crops  in 
the  South,  99 

Dean,  Daniel,  frequent  sprayings, 
343 

Definition  of  potato  grade  terms, 
180 

Definition  of  term  late  or  main  crop 
potatoes  in  South,  100 

Definition  of  tillage,  75 

Dehydrated  potatoes,  354 

Demonstrational  and  instructional 
potato  projects,  477 

DenaifTe  on  humidity,  217 

Denaiffe's  storage  loss  studies,  216 

Department  Agriculture  construc- 
tion costs,  242 

Depreciation  in  value  of  instru- 
ments, 157 

Description  of  S.  tuberosum  by 
Clunius,  371 

Descriptive  list  of  varieties,  485 

Descriptive  terms  that  may  be  em- 
ployed in  describing  varieties, 
479 

Desirabilitv  of  ample  storage  space, 
203* 

Desirabilitv  of  securing  a  good 
stand,  69 


506 


INDEX 


Desirability  of  storing  clean  tubers, 

213' 
Development  of  a  market  for  fancy 

grades,  187 
Development    of    potato    culture    in 

America,  381 
Development    of    potato    culture    in 

France,  380 
Development    of    potato    culture    in 

Great  Britain,  379 
Development   of    potato    culture    in 

India,  381 
Development    of    potato    culture    in 

Prussia,  379 
Development    of    potato    culture    in 

Sweden,  380 
Dextrine,    method    of    manufacture, 

357 
Difficulties  involved  in  potato  breed- 
ing, 394 
Disadvantages  of  one-  and  two-man 

planters,  66 
Disadvantages   of   pitting   potatoes, 

225 
Disease  classification,  247 
Disease  losses  in  storage,  212 
Disinfection  of  storage  house,  212 
Distance   between   rows   and   plants 

in  row,  61 
Distribution  of  common  scab,  265 
Distribution  of  leaf  roll,  279 
Distribution  of  potato  crop,  360 
Domestic  production  of  dehydrated 

potatoes,  356 
Domestic    production    of    dextrine, 

357 
Domestic  production  of  potato  flour, 

354 
Domestic  production  of  starch,  349 
Double-headed  barrel  containers,  193 
Drainage  in  relation  to  pitting,  221 
Draining  the  "tule"  lands  in  Calif., 

88 
Dry  Bordeaux,  331 
Dugout   or   cellar   type   of   storage, 

226 
Dust  spray  equipment,  345 
Dusting  freshly  cut  seed,  60 

Early  attention  to  selection,  415 
Early  blight,  249 
Early  history  of  late  blight,  252 
Early  history  of  potatoes,  369 
Early  marketing  of   southern   crop, 
100 


Early  Ohio  group,  452 

Early  or  truck  crop,  95 

Early  potato  culture  in  England, 
379 

Early  record  of  potato  culture  in 
the  U.  S.,  381 

East,  E.  M.,  high-  and  low-yielding 
hills,  419 

East,  E.  M.,  potato-breeding  tech- 
nic,  394,  401 

East's  classification  of  flowering 
habits  of  varieties,  394 

Eastern  Shore  of  Virginia  Produce 
Exchange,   200 

Economic  importance  of  black  scurf, 
262 

Eel  worm  disease,  318 

Effect  of  bad  handling  of  seed,  6!) 

Eff'ect  of  heat,  15 

Effect  of  hot  sun  on  tubers,  174 

Effect  of  late  irrigation,  86 

p]ffect  of  leaf  roll  upon  yield,  279 

Effect  of  light  on  seed,  212 

Effect  of  light  upon  edibility,  211 

Eff'ect  of  mosaic  on  yield,  278 

Effect  of  soil  on  quality,  14 

Effect  of  too  much  moisture  and  soil 
on  tubers  when  stored,  213 

Efficiency  of  one-  and  two-man 
planters,  66 

I'^lements  necessary  to  supply  po- 
tato plant,  27 

Elevation  of  land  in  relation  to  pro- 
duction, 15 

Elevator  diggers,  170 

Emasculation  of  flowers,  400 

Entrance  way  to  storage  house,  231 

Environmental  influence  on  potato 
plant,  14 

European  potato  mania,  393 

Eustace,  H.  J.,  productive  vs.  un- 
productive plants,  418 

Exhibiting  potatoes,  478 

Extent  and  importance  of  Southern 
crop,  92 

Extent  of  Aroostook  Co.,  Me.,  potato 
crop,  123 

Extent  of  crop  in  Mich.,  Wis.,  and 
Minn.,  136 

Extent  of  Florida  potato  crop,  107 

Factors    determining    character    of 

storage  house,  226 
Factors   governing    size    of    storage 

pile,  213 


INDEX 


507 


Fall  crop  potatoes  in  the  South,  101 

Fancy  grades,   188 

Farm  manures,  30 

Far-Western  states,  141 

Fayville    and    Parrot,    potato    stalk 
weevil,  300 

Fenn's  potato-breeding  work,  391 

Fertilizers,  31,  33 

Field  culture  of  seedlings,  411 

Filling  the  storage  house  by  chutes, 
233 

Findlay's  potato-breeding  work,  392 

Fischer's  selection  work,  417 

Fischer's  starch  variation  in  tubers, 
417 

Fitch,   C.   L.,   relation   of   soil   tem- 
perature and  moisture,  19 

Fitch's    classification    of    varieties, 
439 

Fitch's  construction  costs,  240 

Flea  beetle,  293 

Flea  beetle  trap,  295 

Florida  potato  crop,  107 

Flowering  habit  of  the  potato,  394 

Fluctuation  in  potato  production  in 
the  South,  95 

Fluctuation     in     production     and 
causes,  7 

Food    requirements    of    the    potato 
crop,  27 

Foreign  and  American  storage  losses, 
214 

Foreign    production    of    dehydrated 
potatoes,  356 

Foreign  production  of  potato  starch, 
350 

Foreign  vs.  home  production,  2 

Formalin  treatment,  333 

Forms  of  dry  rot,  257 

Four-lined  leaf -bug,  314 

Fox's  cost  data,  160 

Fraser,  S.,  ventilation  and  tempera- 
ture, 208 

French  potato-breeding  work,  392 
Frequent  sprayings,  343 

Gasoline  engine-operated  diggers,  173 
Gasoline    engine  operated    sprayers, 

345 
Gathering  the  seedballs,  409 
General  practices  regarding  size  of 

seed  piece,  57 
Georgia  as  a  potato  producer,  108 
German  potato-breeding  work,  392 
German  potato  production,  2 


Germinating  tubers  in  trays,  52 

Germination  losses,  218 

Gleason  and  Heffron's  potato-breed- 
ing work,  388 

Glucose  production,  357 

Goff,  E.   S.,  high-   and   low-yielding 
plants,  417 

Good  stands  desirable,  69 

Good  tillage,  75 

Goodrich's  potato-breeding  work,  385 

Grabbling  potatoes,  169 

Grading  for  a  fancy  trade,  187 

Grading  in  the  field,  189 

Graf,  J.  E.,  potato  tuber  moth,  305 

Graf,  J.  E.,  tuber-eating  insect  con- 
trol, 341 

Graph  of  potato  production  in  the 
South,  94 

Graph  of  world's  production,  2 

Greeley,  Colorado  district,  143 

Green  manuring,  28 

Green  Mountain  group,  461 

Green,  S.  N.,  use  of  commercial  fer- 
tilizers, 135 

Greening  and  sprouting  seed  tubers, 
51 

Greig,  R.  B.,  the  sprouting  of  seed 
potatoes,  53 

Grimes,  A.  M.,  handling  and  loading 
Southern  potatoes,  197 

Group     1,  Irish  Cobbler,  443 

Group     2,  Triumph,  445 

Group     3,  Early  Michigan,  448 

Group     4,  Rose,  450 

Group     5,  Early  Ohio,  452 

Group     6,  Hebron,  456 

Group     7,  Burbank,  458 

Group     8,  Green  Mountain,  461 

Group     9,  Rural,  463 

Group  10,  Pearl,  466 

Group  11,  Peachblow,  468 

Group  12,  Up-to-Date,  470 

Growers'  coiiperative  marketing  or- 
ganizations, 199 

Grower's  estimate  of  storage  losses, 
218 

Grubb    and    Guilford,    storage   tem- 
perature, 208 

Giissow,  H.  T.,  powdery  scab,  280 
Giissow,  H.  T.,  wart  disease,  269 

Hallet's  method  of  selection,  416 
Hand-harvesting  implements,  167 
Hand-hoeing,  81 
Hand-operated   sprayers,   344 


508 


INDEX 


Handlinfj  potatoes,  195 
Hardenburg,    E.  V.,    size    of    seed 

piece,  55 
Hardman,    G.,     potato    acreage     in 

Nevada,  150 
Harvesting    implements    and    their 

operation,   167 
Harvesting    potatoes    with    elevator 

digger,   170 
Harvesting  potatoes  with  plow,  168 
Harvesting  the  California  crop,  152 
Harvesting  the  crop,  130 
Harvesting  the  potato  crop   in   the 

U.  S.,  166 
Harvesting  the  seedlings,  411 
Hastings,    Fla.,    cultural    practices, 

82 
Hawkins,  L.  A.,  leak  disease,  270 
Hebron  group,  456 
Henshaw,   H.,   classification   of   Up- 

to-Date   varieties,   471 
Hill  selection  method,  424 
Hilling  or  ridging,   132 
Hogbacks    or    knolls    as    sites    for 

storage  house,  227 
Home  rs.  foreign  potato  production, 

2 
Horse  implements  and  their  use,  168 
Hotel   and   restaurant   demands   for 

special  tubers,  187 
How  to  cut  seed,  58 
How  to   select  promising  seedlings, 

412 
Howard's  construction  costs,   241 
Humidity  content  of  air  in  storage 

house,  210 

Increased  potato  consumption  desir- 
able, 360 
Idaho  Falls,  Idaho,  potato  district, 

149 
Idaho    production    and    commercial 

centres,  149 
Idaho    storage    house    construction, 

242 
Illinois  potato  production,   134 
Illinois  production  centres,  135 
Importance  of  aeration,  210 
Importance    of    late    or    main-crop 
production  in  the  South,  101 
Importance  of  moisture  to  plant,  20 
Importance  of  Southern  crop,  92 
Important  production  factors.  122 
Indiana  potato  production,  134 


Indiana  production  centres,  135 
Industrial  uses  of  the  potato,  348 
Influence   of    season   on   yield   from 

large-    and    small-sized    seed 

pieces,  56 
Injury  to  tubers  in  harvesting,  189 
Insect    and    animal    parasites    and 

their  control.  290 
Insecticides  controlling  leaf-chewing 

insects,  334 
Insecticides   controlling   sucking   in- 
sects, 338 
Insecticides  controlling  tuber-eating 

pests,  341 
Insulated  potato  storage  houses,  233 
Insulating  pitted  potatoes,  224 
Intercropping,  39 
Interior      arrangement      Aroostook, 

Me.,    type    of    storage    house, 

235 
Interior  arrangement  of  storage 

house,  232 
Interplanting  or  intercropping,  39 
Introduction   into  Europe,   371 
Iowa  potato  production,  134 
Iowa  production  centres,   135 
Irrigating  up,  85 
Irrigation  in  Florida,  82 
Irrigation  practices  in  peat  soils  of 

West,  86 

Jones,  L.  R.,  blackleg,  271 
Jones,  L.  E.,  early  blight,  249 
Johnson,  G.  W.,  potato  development 
in  India,  381 

Kansas  production  centres,  and  vari- 
eties, 140 
Kentucky  production,  and  commer- 
cial centres,  116 
Kerosene  emulsion,  manufacture  and 

use,  339 
Kind  of  seed  to  use,  47 
Kinds  of  unsound  tubers,  212 
King,   F.   H.,   moisture  reciuirement 

of  plants,  20 
King's  construction  costs,  240 
Kohler's  variety  classification,  437 
Krantz's   flower-stalk   classification, 

439 
Kremers,  E.,  potato  distilleries,  35S 
Krichaufl,  T.  E.,  H.  W..  early  cul- 

ture  in  England.  379 
Kunkel,  L.  0.,  wart  disease.  269 


INDEX 


509 


Labor-saving  device  for  moving  bar- 
rels, 185 

Land  elevation:  its  relation  to  po- 
tato culture,  15 

Langworthy,  C.  F.,  parts  of  tuber, 
367 

Late  blight  and  its  control,  254 

Late  blight  losses,  247 

Late  blight  rot  in  storage,  212 

Late  or  main-crop  potatoes  in  the 
South,  100 

Late  or  main-crop  production  cen- 
tres, 122 

Leading  environmental  influences  in 
potato  culture,  14 

Leaf-chewing  and  mining  pests,  290 

Leaf-roll,  278 

Leak  disease  of  potato,  270 

Le  Baron,  W.,  potato  leaf  hopper,  315 

Leguminous  plants  as  soil  enrichers, 
28 

Lenne's  variety  classification,  436 

Level  culture,  75 

Level  culture  vs.  hilling  or  ridging, 
132 

Life  historv  of  eehvorm,  319 

Life  history  of  late  blight,  252 

Life  history  of  plant  lice,  310 

Life  history  of  potato  leafhopper, 
315 

Life  history  of  potato  stalk  and 
stem  borer,  298 

Life  history  of  white  grubs,  302 

Light  in  its  relation  to  storage,  211 

Lighting  of  storage  house,  231 

Limitations  of  breeding  and  selec- 
tion, 384 

List  of  varieties  with  descriptions, 
485 

Localities  producing  genuine  second- 
crop  seed,  103 

Localities  w^hei'e  potatoes  are  grown 
in  Florida,  107 

Locality  where  refrigerated  storage 
might  be  used,  236 

Location  of  Aroostook,  Me.,  type  of 
storage  house,  234 

Location  of  storage  house,  226 

Location  of  ventilators  in  storage 
house,  232 

Long  Island,  N.  Y.,  potato  district, 
127 

Long  Island,  N.  Y.,  production  cen- 
tres, 129 


Long  Island,  N.  Y.,  soil  and  climatic 
conditions,   129 

Long  Island,  N.  Y.,  source  of  seed 
supply,  129 

Losses  in  storage  due  to  diseases, 
247 

Losses  in  storage  from  mechanical 
injuries,  212 

Loudon,  J.  C,  early  potato  culture 
in  England,  379 

Louisiana  production  and  commer- 
cial centres,   113 

Low  cost  of  production,  156 

Lutman,  B.  F.,  early  blight,  250 

Lutman,  B.  ¥.,  20  years  of  spray- 
ing, 342 

Macoun,  W.  T.,  strain  tests,  429 
Macrosiphum  salonifolii  Ashm.,  309 
Magnitude  of  crop,  1 
Maine  construction  costs,  235 
Manitoba  potato  production,  500 
Market  a  factor  in  determining  re- 
gions of  greatest  production, 
122 
Marketing  early  Southern  crop,  100 
Marketing  potatoes  successfully,  198 
^Markets  for  midwest  states,  135 
Markham,  C,  translation  Chronicles 

of  Peru,  370 
Maryland  potato  production.   111 
Mass  selection  method,  427 
Mechanical  potato  sizers,  182 
Melhus,  I.  E.,  late  blight,  252 
Melhus,  I.  E.,  powdery  scab,  280 
Merino,  G.,  late  blight,  251 
Mertzel  and  Lengerke's  Agricultural 

Calendar,  215 
Metcalfe,  C.  L.,  flea  beetle  trap,  295 
Method  of  applying  commercial  fer- 
tilizer, 33 
Method    of    attack    in    black    scurf, 

263 
Method   of  collecting  and  applying 

pollen,  402 
Method  of  grading  potatoes,  183 
Method    of    growing    and    handling 

seedlings,  410 
Michigan  potato  production  and  va- 
rieties grown,  136 
Michigan,  Wisconsin  and  Minnesota 

area,  136 
]\Iillardet,  A.,  Bordeaux  mixture,  325 
Miller,  P..  potato  varieties  listed  in 
1731,  379 


510 


INDEX 


Milward,  J.  G.,  early  blight,  250 
Milward's  classification,  438 
Mining  pests,  290 
Minnesota  construction  costs,  240 
Minnesota    potato    production    and 

varieties  grown,  136 
Minimizing  handling  to  reduce  tuber 

injury,  189 
Minimizing  tuber  injury  by  proper 

operation  of  sizes,  192 
Mississippi  potato  production,  112 
Missouri  potato  production,   134 
Mitchell,  W.   S.,  description  of  the 

potato,  374 
Moisture    requirement   of   potato 

plant,  20 
Montana   commercial   varieties,   149 
IMontana  potato  production,   148 
More   and   Dorland,   handling  pota- 
toes, 195 
Morris,  0.  M.,  commercial  centre  in 

Oklahoma,  115 
Morse,  W.  J.,  arsenoids,  338 
Morse,  W.  J.,  blackleg,  271 
Morse,  W.  J.,  powdery  scab,  280 
Mosaic  disease  and  yield  reduction, 

277,  278 
Motive    power    required    to    operate 

elevator   type  of  digger,   170 
Murphy,  P.  A.,  mosaic  reduces  yield, 

278 

Nebraska  production  centres,   138 

Necessity  of  crop  rotation,  38 

Needs  of  the  potato  industry,  358 

Net  necrosis,  282 

Nevada  commercial  districts  and 
varieties,   150 

Nevada  potato  production,   150 

New  Brunswick's  yearly  production, 
500 

New  England  and  Northern  New 
York  potato  area,   130 

New  Jersey  potato  districts,  127 

New  Jersey  practice  in  handling 
newly  dug  potatoes,  175 

New  Jersey  soil  and  climatic  con- 
ditions, 129 

New  Jersey  source  of  seed  supply, 
129 

New  Mexico  potato  production  and 
commercial  areas,   151 

New  York  potato  production  (west- 
ern part),  131 


Nineteenth   century   potato-breeding 

achievements,  384 
Nitrogen   in  its  relation  to  the  po- 
tato crop,  27  I 
Nobbe,    F.,    shrinkage    in    storage,       I 

214 
Nobbe's      experimental      storage 

studies,  214 
Non-elevator  harvesting  implements, 

168 
Non-parasitic  diseases,  248 
Nordman's  cost  data,  163 
North  and  South  Dakota,  Nebraska 

and  Kansas  area,  138 
North   Carolina   potato   production, 

109 
North    Dakota    production    centres 

and  varieties,  140 
Nova  Scotia's  jearly  production,  500 
Number  of  irrigations  necessary  to 

produce    good    crop    of    seed 

tubers,   85 

Object  of  storage,  207 
Objections  to  large  sacks,   194 
Occurrence  and  distribution  of  curly 

dwarf,  283 
Occurrence  and  distribution  of  late 

blight,  251 
Occurrence  and  distribution  of  tuber 

moth,  305 
Occurrence  of  fusarium  wilt,  256 
Occurrence  of  powdery  scab,  280 
Ohio  production  centres,  135 
Oklahoma  production  centres,  115 
One-man  potato  planter,  65 
Ontario's  yearly  production,  500 
Operation  of  mechanical  sizers,  184 
Operation     of     one-     and     two-man 

planters,   65 
Operation    of    the    elevator    digger, 

170 
Opinions    on    storage    temperature, 

208 
Oregon  production  centres,   151 
Oregon's  commercial  varieties,  151 
Organic  matter  in  soil,  23 
Origin  and  earlv  history  of  potato, 

369 
Orton,  W.  A.,  curly  dwarf,  283 
Orton,  W.  A.,  mosaic,  277 
Orton,  VV.  A.,  streak,  275 
Orton,  W.  A.,  verticillium  wilt,  261 
Osburn.  H..  potato  leafhopper,  315 
Other  British  potato  breeders,  392 


INDEX 


511 


Parasitic  diseases,  247 
Paris  green  and  its  use,  334 
Parisot,    Dr.,    storage    temperature, 

208 
Parts  of  a  tuber,  367 
Patch,  E.  M.,  potato  aphids,  310 
Paterson's  potato-breeding  work,  391 
Peachblow  group,  468 
Pearl  group,  466 
Pelton's  cost  data,   162 
Pennsylvania's     potato     production, 

131 
Per  capita  consumption,  358 
Percentage  of  successful  crosses,  404 
Period  of  treatment  with  corrosive 

sublimate,  333 
Period  of  treatment  with  formalin, 

334 
Phillips,  H.,  potato  development  in 

Great  Britain,  379 
Phosphorus    in    relation    to    potato 

crop,  27 
Picking    and    handling    the    tubers, 

174 
Planters  in  use,  65,  66 
Planting   in    "tule"    lands    of    Cali- 
fornia and  Oregon,  90 
Planting  methods,  64 
Plowing  out  potatoes,  168 
Plowing  the  land,  24 
Pollen  viability,  395 
Pollinating  potato  flower,  402 
Poor  handling  of  seed,  69 
Poor  stands,  69 
Popenoe,  E.  A.,  potato  stalk  weevil, 

300 
Potash  in  its  relation  to  potato  crop, 

27 
Potato  as  a  livestock  food,  361 
Potato-barley  rotation,  43 
Potato  blossoming  in  Maine,  125 
Potato  breeding  and  selection,  384 
Potato-breeding  difficulties  and  tech- 

nic,  394 
Potato    breeding    in    Aroostook 

County,  Me.,  125 
Potato   breeding  in   Europe,   391 
Potato  culture  in  America,  381 
Potato  culture  in  France,  380 
Potato  culture  in  Great  Britain,  379 
Potato  culture  in  India,  381 
Potato  culture  in  Prussia,  379 
Potato  culture  in  Sweden,  380 
Potato  culture  in  W.  Va.,  117 


Potato  diseases  and  their  control, 
247 

Potato  distilleries,  358 

Potato  exhibits,  478 

Potato  flour  and  its  manufacture, 
352 

Potato  grades  and  terms,  178 

Potato  grading  and  mechanical 
sizers,   182 

Potato  growing  continuously,  41 

Potato  improvement  by  selection, 
414 

Potato  leafhopper,  occurrence  and 
injury,  315 

Potato  plant  lice,  309 

Potato  production  costs,   156 

Potato  production  in  Canada,  11,  12 

Potato  production  in  North  Amer- 
ica, 7 

Potato  production  in  the  South,  92 

Potato  production  in  the  United 
States,  2 

Potato  production  in  U.  S.  by  geo- 
graphical areas,  12 

Potato  products,  348 

Potato  silage,  361 

Potato  sizers,   182 

Potato  sorting  table  or  rack,  186 

Potato   stalk,  and  stem-borers,   298 

Potato-stalk  weevil,  300 

Potato  starch  and  its  manufacture, 
348,  352 

Potato  storage  and  storage  shrink- 
age, 207 

Potato  trips,  482 

Potato  tuber  moth,  304 

Potato  tuber  parts,  367 

Potato  wart  disease,  269 

Potatoes  after  alfalfa,  42 

Pounds  of  water  to  produce  pound 
dry  matter,  20 

Powdery 'scab,  280 

Pratt,  0.,  distribution  of  common 
scab,  265 

Pre-germination  tillage,  76 

Preparation  of  Bordeaux  mixture, 
325 

Preparation  of  seed  bed,  26 

Prince  Edward  Island's  potato  pro- 
duction,  500 

Pringle's  potato-breeding  work,  387 

Preventive  measures  for  black  scurf, 
264 

Preventive  measures  for  common 
scab,  266 


512 


NDEX 


Preventive  measures  for  e  a  r  1  v 
blight,  250 

rreventivi'  measures  for  fusariuni 
diseases,  260 

Preventive  measures  for  leak,  271 

Preventive  measures  for  silver  scurf, 
268 

Preventive  measures  for  verticil- 
lium  wilt,  262 

Preventive  measures  for  wart  dis- 
ease, 270 

Production  centres  in  the  South,  90 

Productive  rs.  unproductive  hills 
(East),  419 

Productive  I's.  unproductive  hills 
(Eustace),  418 

Productive  rs.  unproductive  hills 
(Waid),419 

Proper  loading  of  hampers,   196 

Proper  loading  of  sacks  or  barrels, 
195 

Proper  loading  of  summer  ship- 
ments, 195 

Proper  loading  of  winter  shipments, 
196 

Proper  stage  for  emasculating 
flowers,  400 

Provision  for  filling  storage  house, 
233 

Provision  for  ventilating  pitted  po- 
tatoes, 223 

Putsch  and  Vertuch  classification, 
435 

Pyrox  as  a  fungicide,  331 

Pyrox  as  an  insecticide,  338 

Quality  of  second-crop  seed,  106 
Quebec's  yearly  production,   500 

Rainfall   in    its   relation    to    potato 

crop,  21 
Rand's  potato-breeding  work.  388 
Rands,  R.  D.,  early  blight,  250 
Rate  and  distance  of  planting,  61 
Receptacles    used   in    gathering    tu- 
bers, 175 
Reclamation  of  "tule"  lands  in  Cal- 
ifornia, 88 
Reduction   of   mechanical    injury  of 

tubers,  172 
Reed's   description    of   tuber-bearing 

stolons,  365 
Refrigerated   ])otato  storage  houses, 
236 


Relation  of  commercial  centres  to 
markets,   199 

Relation  of  rainfall  to  storage  house. 
230 

Relation  of  size  of  seed  piece  to 
amount  used,  55 

Relation  of  size  of  seed  piece  to 
spacing,  64 

Relation  of  sugar  accumulation  to 
temperature,  210 

Relation  of  temperature  and  mois- 
ture to  storage  losses,  212. 
218 

Relation  of  temperature  and  mois- 
ture to  tuber  production,  15. 
21 

Relative  importance  of  early,  late, 
and   fall  crop,   93 

Relative  importance  of  potato  crop 
in  U.  S.,  3,  4 

Relative  magnitude  of  crop,  1 

Remedial  measures  for  Colorado 
beetle,  293 

Remedial  measures  for  common 
scab,  265 

Remedial  measures  for  eelworm,  320 

Remedial  measures  for  flea  beetle, 
295 

Remedial  measures  for  four-lined 
leaf -bug,  314 

Remedial  measures  for  plant  lice, 
312 

Remedial  measures  for  potato  leaf- 
hopper,  318 

Remedial  measures  for  tliroc-liiuvl 
potato  beetle,  290 

Removing  the  potato  seeds,   40!) 

Respiration  and  svntlicsis  e(|nili- 
brium,  210 

Resultant  benefits  from  fungicides 
and  insecticides,  342 

Rhizoctonia  or  black  scurf,  202 

Riced  potatoes,  355 

Richter,  W.,  potato  breeding  in 
Germany,  392 

Ridge  culture,  74 

Roberts  and  Clinton  iillage  studies, 
132 

Roof  construction  of  dugont  storage 
house,  229 

Rose  group,  450 

Round  and  Gore,  potato  silage,  361 

Ruggles  and  Graham,  potato  leaf- 
hopper,  315 

Rural  group,  463 


INDEX 


513 


Salamaii,    R.    N".,    potato    breeding, 

401 
San  Luis  Valley  district,  147 
Saskatchewan,  yearlj'  production  of, 

500 
Schroeder's   construction    costs,   240 
Schultz,  E.  S.,  powdery  scab,  281 
Score  card,  its  use  in  judging,  479 
Seasonal    influence   on   size  of    seed 

I)iece,  56 
Second-crop     cultural     practices     in 

South,  103 
Second-crop     potato    production    in 

South,  103 
Seed  bed  preparation,  26 
Seed  cutting,  58 

Seed  plot  method  of  selection,  428 
Seed  potato  containers,  192 
Seed  potato  develoi)ment  work,  428 
Seed  treatment  after  cutting,  60 
Seed  treatment  with  corrosive  sub- 
limate and  formalin,  333,  334 
Selecting  and   preparing   exhibition 

tubers,  478 
Selecting    promising   seedlings,    412 
Selection    as    a   means    of    improve- 
ment, 414 
Selection  methods,  420 
Seven-year  crop  rotation  system,  43 
Shape  of  pile  in  pit  storage,  222 
Shima,  G.,  the  potato  king,   152 
Shipping  and  marketing  a  business 

operation,    192 
Shipping   potatoes   to   distant   mar- 
kets, 195 
Shrinkage  due  to  transpiration  and 

respiration,  214 
Silaging  potatoes,  361 
Silver  scurf,  267 
Size    of    Aroostook    County    potato 

crop,   123 
Size  of  crop   should   influence  time 

of  selling,  202 
Size  of  seed  pieces,  54 
Size    of    seed    pieces    on    irrigated 

land,  57 
Size  of  storage  bin,  213 
Size  of  tuber  pile  in  pitting,  223 
Skinner,   R.  P.,  alcohol  production, 

358 
Sliced  dried  potatoes,  355 
Slime  mold,  248 

Smith,  W.  J.,  climatic  influence,  15 
Snell's  classification,  439 

J     33 


Sod  walls  in  storage  house  construc- 
tion, 228 
Soft  rots,  273 
Soil  adapted  to  late  crop  in  South, 

101 
Soil  and  climatic  conditions  in  Long 

Island  and  New  Jersey,  129 
Soil  for  early  crop,  96 
Soil  preparation,  24 
Soil  requirements,   14 
Soil  sanitation,  38 
Soil  types  in  tlie  South,  97 
Soils  deficient  in  nitrogen,  27 
Soils  of  Aroostook  County,  Me.,  123 
Solution  of  high  cost  of  production, 

164 
Soundness  of  tubers  stored,  212 
Source  of  early  blight  infection,  250 
Source  of  seed  for  L.  I.  and  N.  J., 

129 
Sources  of  Southern  seed  supply,  98 
South    Carolina,   potato   production, 

108 
South  Dakota  potato  production,  138 
Southern   potato  production  graph, 

94 
Spacing  of  seed  pieces,  62 
Spacing  of  ventilators,  232 
Special  cultural  features,  82 
Species  of  fusarium,  257 
Spindling  sprout,  282 
Spongospora  subterrannea  (powderv 

scab),  280 
Spray  equipment,  343 
Spray  equipment  classification,  345 
Stabilization  of  farm  prices,  204 
Starch  imports,  351 
Starch  manufacture,  348 
Starch  variation  in  tubers,  417 
Starch  yields,  349 
Stem-  and  tuber-eating  insects,  290 
Stewart,    F.    C,    late   blight    losses, 

247 
Stockton,    Calif.,    harvesting    prac- 
tices, 176 
Stone,  J.  L.,  level  vs.  ridge  culture, 

132 
Storage  capacity  per  cubic  foot,  239 
Storage  cost,  239 
Storage  house  arrangement,  232 
Storage  house  humidity,  210 
Storage  houses  proper,  225 
Storage  losses,  214,  218 
Storage  temperature,  207 
Storage  unsound  tubers,  212 


514 


[XDEX 


Strain  test  studies,  429 

Straw  as  an  insulator  and  moisturu 

absorbent,  231 
Strawberries  with  potatoes,  41 
Streak,  274 
Structure  of  pistil  of  potato  flower, 

396 
Structure     of     stamens     of     potato 

flower,  397 
Stuart,  \V.,  potato  breeding,  'M)'y 
Stuart's  classification,  439 
Student's     potato-growing     project, 

475 
Successful    merchandising    of    crop, 

156 
Successful  operation  of  an  elevator 

digger,  171 
Sucking  insects,  291 
Sugar  accumulation  in  potato,  210 
Suggestions  for  spraying  plant  lice, 

341 
Suggestive  potato  descriptive  terms, 

479 
Suitable  cars,  lO" 
Sun  scalding  tubers,  174 
Sweet  potato  storage  house  construc- 
tion, 234 
Sweet  ranch  construction  costs,  2.!'.) 
Sweet's  type  of   storage  house,  234 
Symptoms  of  black  scurf,  262 
Symptoms  of  early  blight,  250 
sVmptoms  of  fusarium  wilt,  2r)() 
Symptoms  of  leaf-roll,  278 
Symptoms  of  verticillium  wilt,  201 
Systematized   Bordeaux   m  i  x  t  u  r  e 

making,  328 
Systems  of  crop  rotation,  38 
Systems  of  culture,  74 

Table  of  contents,  IX 
Taft  and  Hcdrick,  storage  losses,  217 
Technic  in   potato  breeding,  39(5 
Temperature   conditions   in   relation 

to  crop,  15 
Temperature,  storage,  208 
Tennessee  production   and   commer- 
cial sections,  116 
Texas  potato  sizer,   185 
Texas    production    and    commercial 

sections,  114 
The  early  or  truck  crop  in  the  Soutli, 

95 
The  fall  crop  proper,  102 
The  "Far-Western"   states,   141 
The  five-eighth-bushel  basket,  194 


The  potato  essentially  a  northern 
crop,   121 

The  potato  king,  152 

The  soil  and  its  preparation,  23 

Thermographic  record  sheets,  238 

Thompson,  H.  C,  sweet  potato  stor- 
age house  construction,  234 

Three-lined  potato  beetle,  296 

Three  steps  in  making  Bordeaux 
mixture,  326 

Three-year  crop  rotation  system,  43 

Tillage,  75 

Tillage  after  germination,  78 

Tillage  studies,  132 

Time  of  delivery  of  Northern  seed 
in  Soiith,'98 

Time  of  planting  fall  and  second 
crop  in  South.  106 

Time  to  sell  crop,  200 

Tip-burn,  284 

Tortoise  beetles,  297 

Tractor-operated  sprav  c(iuipim'iit, 
344,  345 

Transmission  of  productivity,  417 

Treatment  of  seed,  332 

Treatment  of  seed  after  cutting,  GO 

Truax,  H.  E.,  potato  grades,  178 

Tuber-bearing  stolons,  365 

Tuber-eating  insect  control,  341 

Tuber  injiiry  from  common  scab,  264 

Tuber  modification  due  to  heat  and 
drought,  16 

Tuber  moth  injury,  307 

Tuber  unit  selection  method,  420 

Tuber  variations,  420 

Twentieth  century  progress  in  breed- 
ing, 393 

Twenty  years  of  spraying,  342 

Twin  "Falls  and  Blackfoot,  Idalw), 
districts,   149 

Two-bushel  or  120-pound  sack  con- 
tainer, 193 

Two-horse  riding  cultivator,  78 

Two  important  production  factors, 
122 

Two-man  planters,  65 

Types  of  elevator  diggers,  170 

Types  of  mechanical  sizers,  183 

Types  of  planters,  65 

Types  of  potato  containers,  193 

Types  of  storage  houses,  221 

Ultra-microscopic  organisms,  248 
United    States    Dept.    Agr.    storage 
house,  212 


INDEX 


515 


United  States  potato  grades,   17S 

Up-to-Date  group,  470 

Use  of  commercial  fertilizers,  ;!1 

Use  of  farm  manures,  30 

Use  of  new  l)urlap  sacks,  193 

Use  of  the  two-horse  riding  culti- 
vator, 78 

Use  of  the  weeder  and  spike-toodi 
harrow,  76 

Use  of  ventilated  cars  for  sunuiier 
shipment,  197 

Uses  of  potato  starch,  349 

Utah  production  and  commercial 
centres,  151 

Value  of  farm  manures,  30 

Van  Orman's  potato-breeding  work, 

390 
Van  (Slyke,  L.  L.,  chemical  elements 

in  plants,  27 
Variation  observations,   41(i,  420 
Variations,  tuber,  420 
Varieties  growing  in  "Far-Western" 

states,  141 
Varieties  growing  in  !Maine,  124 
Varieties  grown  in  N.  D.,  S.  D.,  Neb. 

and  Kan.,  140 
Varieties  grown  in  South  for  early 

crop,  97 
Varieties   grown    in    South    for    late 

crop,   101 
Varieties  grown   in   South  for  main 

crop,   101 
Varieties  grown  in  South  for  second 

crop,   103 

^'arieties  listed: 

Acme    (Early  Acme).  5,'  456,  4S5 

Acme  (Walker's),  5,  4S.1 

Acorn,  485 

Admiral  Foote,  485 

Advancer.  Vicks'  Farlv,  6,  48") 

Albino    (Early  Albino,'  etc.),  3,  48.1 

Alpha,  485 

American  Giant,  8-2,  463,  485 

American  Wonder,  71,  485 

Arcadia,  9-1,  466 

Aroostook  Beauty,  485 

Babbitt,  8-1,  485' 

Badger  State,  485 

Banner    (Livingston's  Banner),  91, 

466.  485 
Banner,  485 
Beauty    (Brownell's  Beauty).  485 


IJeauty  of  Hebron   (Earlv  B.  of  H. ) , 

'6,  457,  485 
Beauty  of  Hebron    (Improved  B.  of 

'  H. ) ,  6,  457 
Beautv  of  Hebron    (Late  B.  of  II.), 

"6,  457,  485 
Belle,  485 

Bethel  Beautv,  8-1,  463,  485 
Bill  Nve,  485 
Bishop's  Pride,  8-1,  463 
Blight  Proof,  81,  485 
Blightless     (Late    Blightless),    8-1, 

403,  485 
Blightless  Wonder,  8-1,  463,  485 
Blue  Victor,  10-3,  468,  485 
Blush    (Rural  Blush,  etc.),  485 
Bovee    (  Farly  Bovee),  6,  486 
Brown  Beauty, 
HrowiU'U's  Best,  486 
Buuless  (Gurncy's  Bugless  ) ,  8-1,  463 
Bull  -Moose,  12,'  471 
Burl)ank    (Burbank    Seedling),    7-1, 

460,  486 
Cambridge  Pvusset,  7-2,  460 
Carman  No.   1,  82,  463,  486 
Carman  No.  3,  9-1,  466,  486 
Charles  Downing  ( Idaho  Kural ) ,  486 
Chicago  Market,  5,  486 
Clark's  No.  1,  4-1,  451,  486 
Clyde,  8-1,  463,  486 
Colonel  Stanlev,  12,  471 
Columbus,  6,  457,  486 
Conquering  Hero,  12,  471 
Cottar,  12,  471 

Country  Gentleman.  6,  457,  486 
Crown  Jewell,  6,  457 
Cummings  Pride,  12,  471 
Dakota  Red,  486 
Dakota  Seedling,  486 
Dalhousie,  12,  471 
Dalmeney  Argon,  12,  471 
Dalmeney  Beauty,  12,  471 
Dalmeney  Helium.  12,  471 
Dalmencv  Hero.  12,  471 
Dalmene'v  Begent.  12,  471 
Dearborn,  IQ-l,  468,  486 
Delaware.  8-1,  463,  486 
Dew  Drop,  3,  448 
Dooley's,  91,  466 
Doolin,  John,  9-1,  466 
Duchess  of  Buccleugh,  12,  471 
Duchess  of  Cornwall,   12,  471 
Early  Acme,  see  Acme 
Earlv  Albino,   see   Albino 


1  The  numbers  in  Black  refer  to  the  group  to  which  they  belong. 


516 


INDEX 


Early  Beauty,  1,  445 

J'^aily  Bovee,  see  Bovee 

Early  Dixie,  1,  445 

JOarly  Durham.  4-1,  451 

JOarly  iMireka,  1,  445 

Early  Fortuue,  4,  451 

Early  Harvest,  3,  448,  48() 

EarlV  Harvest,  6,  486 

Karlv  Maine,  4-1,  451,  480 

Karl'v  Manistee,  4-2,  452.  480 

Early  Market,  5,  45(>,  487 

Early  Mayflower,  487 

Early  Michigan,  3,  448,  487 

Early  Norther,  4,  487 

Early  Ohio,  5,  456,  487 

Earl'y  Peaehblow,  11-1,  470 

Early  Petoskey,  1,  445 

Early  Prospect,  2,  448 

Early  Puritan,  3,  448,  4'.)0 

Early  Pvose.  4-1,  451,  487 

]':arly  Six  Weeks,  5,  456 

Early  Standard,  1,  445 

Early  Sunrise,  4-1,  451 

Early  Thoroughbred,   4-1,   451 

Early  Vermont,  4-1,  451 

Early  Victor,  1,  445 

Early  Walters,  4-1,  451 

Early  Waulionsie,  1,  445 

Ehnola,  3,  448 

Empire  State,  8-2,  463,  487 

Enormous    (North   Star),  81,   487 

Enquirer,  12,  471 

Eureka   (Brownell's  Eureka),  487 

Eureka    (Ex.  Early  Eureka),  1,445. 

487 
Everitt,  487 
Excelsior,  487 

Excelsior    (Early  Excelsior).  5,  487 
]']xcelsior  (  Ex.  Early  Excelsior ) ,  487 
]-:xtra  Early,  487 
]5xtra  Early  Eureka,  see  Eureka 
Extra    Early    Fillbasket,    see     Fill- 

Extra  Early  Sunlight,  3.  448 
lOxtra  Early  Vermont,  4-1,  -151 
Factor,  12,471 
Farmer  ( Farmer  Hastings) ,  81,  4{):!. 

487 
Fillbasket,  487 
Fillbasket    (Ex.    Earlv    Fillbasket), 

4-1,  451,  487 
First  Earlv,  1,  445 
Flourball,   1,  445.  487 
Freeman,  8-1,  46:}.  487 
tiarnot  Chili,  487 


Gem  of  Aroostook,  6,  457,  487 
General  Roberts,  12,  471 
Gold  Coin.  8-1,  403,  487 
Gold  Standard,  12,  471 
Golden  Harvest,  9-2,  400 
Golden  Rule,  9-2,  400 
Golden  Rural,  9-2,  40() 
Golden  Russet,  7-2,  400,  487 
Great   Divide,  9-1,  400,  488 
Green  ^Mountain,  8-1,  4(i;},  488 
Green  ^Mountain  Jr.,  8-1,  403,  488 
Green   ^Mountain,  Lowell's,  8-1,  463, 
Hajjpy  ^Medium,  1,  445 
Harbinger,  6,  457,  488 
Hart's  No.  1,  9-1,  406 
Hastings,  see  Farmer 
Heather  Blossom,   12,  471 
Heavyweight      ( Everitt's     H  e  a  v  y- 

weight),   488 
Heavyweight   (Mill's  Heavvweight) , 

488 
Highlander.  12,  480 
Honeoye  Rose,  2,  448 
Hoosier    (not   sj-n.    of   McCormick ) . 

6,  488 
Houlton  Rose,  4-1,  451 
Improved  No.  5,  9-1,  460 
Improved  or  Perfect  Peaehblow,  11-2, 

470 
Irish  Cobbler,   1,  445,  488 
Irish  Daisy,  1,  445 
Isle  of  Jersey,  9-1,  466 
Jackson  White,  9-1,  460 
Jersey    Peaehblow     (Old    J.    Peach- 

'  blow),  11-1,  470.  488 
Jones  Pink-Eved  Seedling,  488 
Joseph,  488 

June    Eating     (Craine's    June    Eat- 
ing), 488 
Junior  Pride,  6,  457 
Keeper    (Craine's  Keeper).  4SS 
Keystone,  8-1,  463,  488 
Kiiig,  4-2,  452 
King  Loth,  12,  471 
Klondike,  9-1,  488 
Knowle's    (Knowle's   Big   Croitper). 

488 
Late   Beauty    (Heath's   L.    B.),   !M. 

466 
Late  Blight  less,  8-1,  403 
Late  Ohio.  5,  456,  488 
Late  Petoskey,  9-2,  460 
Late  Puritan,  7-1,  460,  400 
Late  Rose,  4-1,  451 
Late  Surprise,  9-1,  466 


INDEX 


517 


Late  Victor,  9-1,  466 

Lee's  Favorite,  4-1,  488 

Lightning   (Criiie'.s  Lightning),  488 

Lily  ^^"hite,  9-1,  466 

Long  Ishmd  W'under,  8-1,  46o 

Longfellow,  8-2,  463 

McCormifk    (Late  Hoosier,  Lookout 

ilountain),  IM,  470,  488 
McCormick      (White     McC'orniick ) , 

11-1,  470 
McGregor,  8-1,  463 
McKinley,  8-1,  463 
Maggie    -Murphv     (Queen    of    the 

West),  480 
Magnum  Bonuni,  480 
Majestic,  5,  4r)6 
IMammoth  Pearl,  480 
Manila,  9-1,  466 
Manistee,  4-2,  452 
Market  Prize,  91,  466 
Million  Dollar,  91,  -^^^G 
Mill's  Pride.  81,  463 
Milwaukee.  6,  457 
Money  Maker,  7-1,  460,  480 
Moreton,  12,  471 
Nebraska,  9-1,  466 
Netted  Gem,  7-2,  460 
New   Improved   P  e  a  c  h  b  1  o  w 

(Nichol's),    11-2,  470 
New  Oregon,  8-1,  463 
New  Queen,  6,  457,  480 
New  White  Peachblow,  11-2,  470 
New  White  Victor,  1,  445 
New  Wonderful  7-2,  460 
Nobleman,  12,  471 
Non-Blight,  9-1,  466 
Norcross,  8-1,  463,  489 
Noroton  Beauty,  2,  448,  489 
North  Star,  489 
Northern  Beauty,  4-1,  451 
Nott's  Peachblow,  11-2,  470 
Noxall,  9-1,  466,  489 
Ohio  Junior,  5,  489 
Ohio  Wonder,  9-1,  460 
Orange   (Wall's  Orange),  489 
Pan-American,  9-1,  466,  489  ' 
Pan-American,  489 
Peachblow    (Ex.  Early  Peachblow), 

11-1,  489 
Peachblow       ( Perfect      Peachblow ) , 

11-2,  470,  489 
Peachblow      (Thorburn's     New     W. 

Peachblow),    H-l,  489 
Pearl    (Peerless),   IQ-l,  468.  480 


Pearl  of  Cannon  Valley,  480 

*Peerless  (Bresee's  No.  6  or  Bos- 
ton), 9-1,  466,  489 

People's,  10-2,  468,  480 

I'ingree,  489 

Potentate,  1,  445,  489 

Potentate,  9-1,  466 

Preparation  of  drj^  Bordeaux  mix- 
ture, 331 

I'resident  Roosevelt,  12,  471 

Pride,  8-1,  463 

Pride  of  Multnomah,  7-1,  489 

Prince  Henry,  9-1,  466 

Prize  Earlv  Dakota,  5,  456 

Producer,   12,  471,  490 

Prolific  Bresee's  (Bresee's  No.  2), 
490 

Proper  loading  of  cars,  195 

Prosperity,  91,  466,  490 

Puritan,  Early,  see  Early  Puritan 

Puritan,  Late,  see  Late  Puritan 

Quick  Crop,  6,  457 

Quick  Lunch,  2,  448,  490 

Patckin's  Red  River  Special,  5,  45(i 

Rehoboth,  IQ-l,  468 

Rhind's  Hybrid,  9-1,  466 

Rochester  Rose,  4-1,  451 

Rural  New  Yorker  No.  2,  9-1,  466. 
490 

Russet  Burbank,  7-2,  460,  490 

Russet  Rural,  9-2,  464,  490 

Rustproof,  8-2,  463,  490 

Rusty  Coat,  7-2,  460 

Scabproof,  7-2,  460 

Scottish   Monarch,    12,   471 

Scottish   Triumph,   12,  471 

Seneca  Beauty,  490 

Sensation,  9-1,  466 

Sensation,   12,  471 

Silver  King,  8-1,  463 

Silver  Skin,  490 

Sir  Mark  Stewart,  12,  471 

Sir  Walter  Raleigh,  9-1,  466,  490 

Snow.  8-1,  463,  490 

Snowflake,  490 

Solanum  species  from  S.  A..  12,  471 

Somer's  Extra  Earlv,  4-1,  451 

Spaulding  No.  4,  4-2,  452.  490 

Star-of-the-East,  6,  457,  490 

State  of  Maine,  8-2,  463,  491 

Superlative,  12,  471 

Surprise   (Early  Surprise),  1,  491 

Table  Talk,   12*  471 

Talisman.  12,  471 


Not  the  true  Bresee's  No. 


518 


INDEX 


Thorlmrn,  4-1,  451,  491 

Todd's  Wonder,  9-!,  466 

Triumpli,  2,  448,  491 

Trust  Buster,  1,  445 

Uncle  Sain,  8-1,  4fio,  401 

Uncle  Sam,  9-1,  466 

Verljots   (from  S.  A.h  12,  471 

Victor   (Early  Victor),  1,  445,  491 

Vigorosa,  6,  457 

Warrior,  12,  471 

Washington,  8-1,  463 

White  Elephant,  6,  457,  491 

White  Giant,   9-1,  466 

White  Globe,  9-1,  466 

White  Harvest    (Gnrney's    W.    H. ) , 

8-1,   463,   491 
Whho  Hebron,  6,  457 
White  Mammoth   ( Whiton's  W.  M.) , 

8-1,  491 
White  Ohio,  5,  456,  491 
White  Rose,  4-1,  451,  491 
^^"hite  Star,  7-1,  491 
White  Swan,  9-1,  466 
White  Triumph,  2,  448 
Wood's  Earliest,  2,  448 
World's  Wonder,  9-1,  491 

Varieties  to  grow,  46 
^'entilated  storage  house  floor,  232 
Ventilation  for  pitted  tubers,  223 
Ventilation    in    storage    house,    211, 

231 
Ventilator   construction,   232 
Verticillium  wilt,  261 
Vilmorin,   Ph.   de.,  early  culture   in 

France,  380 
Vilmorin's  activities  in  France,  392 
Vilmorin's  classification,  436 
Virginia  production,  119 

^^'aid,  C.  W.,  high-  and  low-yielding 
plants.  410 

\\'all  construction  of  storage  liouses, 
229 

Wart  disease,  269 

Washington  production  and  com- 
mercial centres,   151 

Water  transportation  quickest  and 
safest,  197 


Watson,  J.  F.,  early  record  potato 
culture  in  America,  381 

Webber,  H.  J.,  tuber-unit  method, 
420 

West  Virginia  production  and  com- 
mercial centres,   117 

\\estern  New  York  and  Pennsyl- 
vania region,  131 

Western  type  of  mechanical  sizer, 
184^ 

Westover  and  Rowe,  soils  of  Aroos- 
took Co.,  Me.,   123 

Whale  oil  soap,  340 

When  should  a  grower  scH,  200 

When  to  cut  seed,  59 

White  grubs,  habits  and  life  history, 
302 

Why  import  starch,  351 

Widtsoe,  J.  A.,  moisture  require- 
ments of  plants,  20 

Wight,  W.  F.,  early  history  of  the 
potato,  369 

Wight's  comments  regarding  ^'ir- 
ginia  origin,  372 

Wing  potato  hoe,  78 

Winter  shipments  by  rail,   196 

Wireworms :  habits  and  life  history, 
304 

Wisconsin  production  and  varieties 
grown,  136 

Wortlev,  C.  J.,  mosaic  reduces  yield, 
278 

Wright  and  Castle,  storage  tempera- 
ture, 208 

Wyoming  production  and  commer- 
cial centres,  147 

Yearly  and  average  production  by 
Cajiadian  provinces,  500 

Yearly  and  average  production  by 
states,  492 

Yields  fnmi  fall  and  second-crop 
idanting,    106 

Zcllcr,  P.  C,  potato  tuber  moth,  305 
Zone    car    movement    in    Aroostook 
Co.,  Me.,  126 


North  Carofina  State 


POTATO  ITS  CULTURE  USES  HISTORY 


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